When Mazda launched the RX-8 in 2003, it put the Wankel rotary engine back into the mainstream. The car was well received by motoring press all around the world, but as time has gone by the RX-8 has developed a bit of a reputation for being unreliable.
In reality, this reputation probably has more to do with the fact that RX-8s can be purchased cheap and they are often not maintained well. That’s why we have created this Mazda RX-8 buyer’s guide. If you are looking to purchase a RX-8, this guide will give you all the information you need to know, so you don’t wind up with a lemon.
How To Use This Mazda RX-8 Buying Guide
This is a long guide, so make sure you use the table of contents below to skip to the section you want to read (or read it all). To start with, we will be looking at the history and specifications of the Mazda RX-8. Following that we will be delving into the buyer’s guide section of the article. At the end of the guide, we have information on how to import a RX-8 from Japan, what to look for in the seller and where to find them for sale.
History of the Mazda RX-8
Rotary engined cars were an integral part of Mazda’s sportscar line up from the 1960s to the end of the RX-8’s production run. Their first Wankel rotary powered production car was the 1967 Cosmo. Mazda pressed ahead with the rotary design and in 1972 the company would introduce the RX-2, the first in a long line of incredible RX series cars.
The most famous of these rotary powered RX cars would be the RX-7. Altogether, Mazda launched three different generations of the RX-7 starting in 1978 and finishing in 2002. With the conclusion of the RX-7 linage, Mazda needed to create something special that would bring their rotary sportscar range into the 21st century.
What they came up with was the RX-8. The Mazda RX-8 was essentially a combination of the RX-7 and Cosmo (exclusive to Japan). The car was more practical than the much-loved RX-7, but more sporty than the Cosmo.
The original design of the RX-8 can be traced back to the RX-01 concept car. This featured an early iteration of the 13B-MSP engine and was designed as a compact, simple, inexpensive and fun-to-drive car that was more like the first gen RX-7 rather than the spaceship like third generation model.
Due to the company’s financial position at the time and the growing demand for SUVs, Mazda put a hold on the RX-01’s development. However, a team of engineers kept the development of the 13B-MSP engine alive by using a modified MX-5 chassis. This work was noticed by management at the Hiroshima based manufacturer and development of the engine was further advanced.
The 13B-MSP engine would eventually turn into the RENESIS engine and it would debut alongside the EVOLV concept car, which featured suicide rear doors like the final production version of the RX-8. Mazda further refined the styling of the concept car by making its Japanese, United States and European studios compete for the best design.
The project was headed up by Ikuo Maeda, the son of Matasaburo Maeda (the lead designer of the original RX-7). Approval for the RX-8 project was given on one condition, the final production car needed to have four doors. This condition was partly due to Ford’s influence (They owned a large portion of Mazda at the time).
Mazda unveiled the concept car in 2001 and a near-production version of the RX-8 was displayed a few months later at the 2001 Tokyo Motor Show. The final production car closely resembled the one at the Tokyo Motor Show, but it would not launch until February 2003.
The Production RX-8
The RX-8 was designed as a front-engined, rear-wheel-drive, four-door quad coupe. It featured a near 50:50 weight distribution and a low polar moment of inertia, which was achieved by mounting the engine behind the front axle and placing the fuel tank ahead of the rear axle.
Mazda’s engineers incorporated a double wishbone suspension setup at the front and a multi-link setup at the rear. Much of the body was manufactured out of steel, however, some parts were made from aluminium and plastic to save weight.
Engineers at Mazda crafted the manual gearbox’s driveshaft out of a carbon fibre composite to reduce rotational mass connected to the engine. They also fitted the car with a torque-sensing conical limited-slip differential for improved handling.
Despite being underpowered compared to its predecessor, the RX-8 was praised for its driving dynamics and clever engineering. The rear-hinged “freestyle” doors (similar to suicide doors) were a prominent feature of the RX-8, making it much more practical than the RX-7. Additionally, the RX-8’s cabin was designed to allow enough room for four adults, making it genuine 4-seater rather than a 2+2.
First Series RX-8 (2003 – 2008)
Early models of the RX-8 were given chassis codes SE3P and JM1FE. Production started in 2003, however, the cars U.S debut was for the 2004 model.
This first-generation RX-8 models was powered by a 1.3-litre RENESIS 13B-MSP (2-rotor, multi-side-port) Wankel engine. Initially, Mazda offered the RX-8 with a couple of engine and transmission options. We have listed these below.
4-Port RENESIS Model
- 189 – 197 hp (depending on the transmission and location it was sold)
- 5-speed manual or 4-speed automatic transmission
- Sport Suspension package optional
6-port high power RENESIS Model
- 228 – 232 hp (depending on the location it was sold)
- six-speed manual transmission
- These models automatically got the Sport Suspension package
The main difference between the 4-port and the 6-port is that the latter has 2 more intake ports than the former. This means that more air can flow into the engine at high engine speeds. A 4-port engine beyond 7,500 rpm can’t get enough air, whereas a 6-port engine can. However, increasing airflow at higher rpms reduces airflow optimisation at lower engine speeds. As a result, the 4-port has a few more ft/lbs of torque than the 6-port.
RX-8 Generation One Options
- 2004 – 2005 – 4 speed Automatic transmissions (North America): 4-port engine
- 2003 – 2008 – 4 speed Automatic transmissions (Europe): 4-port engine
- 2006 – 2008 – 6 speed Automatic transmissions (paddle shift available): 6-port engine (was not sold in Europe)
- 2003 – 2008 – 6 speed Manual transmissions: 6-port engine
- 2003 – 2008 – 5 speed Manual transmissions: 4-port engine (was not sold in North America)
Special Edition Models & Kits
In 2003 Mazda announced a Mazdaspeed version of the RX-8 that was exclusive to Japan. It was based on the Type S model and was tuned by Mazda’s in-house racing division Mazdaspeed. These cars featured a number of performance and accessory upgrades over the standard RX-8.
- Performance exhaust
- Upgraded spark plugs
- Grounding kit
- Lightweight flywheel & Re-balanced eccentric shaft
- Performance brake pads
- Stiffer anti roll bars
- Four-point front strut tower brace and rear strut tower brace
- Adjustable coilovers
- New front bumper, side skirts and rear wing
A total of 480 factory Mazdaspeed RX-8s were produced. These were available in either Strato Blue Mica, or Sunlight Silver Metallic as exclusive colours. Mazda also sold Mazdaspeed accessories worldwide through their dealerships, so some models have been upgraded to the Mazdaspeed spec.
Mazda introduced the NR-A kit for Type S RX-8s in January 2004. It was approved by the Japan Automobile Federation (JAF) and was designed to bring the RX-8 up to spec so it could participate in the one-make Party Race sanctioned by JAF. The kit featured a roll bar, sports radiator, oil-cooler kit, tow hooks, and racing brake pads.
Sports Prestige Limited or Shinka
Mazda introduced the “Sports Prestige Limited” in Japan in 2005 and the “Shinka” in North America in 2006. The Shinka takes its name from the Japanese word meaning “transformation” or “evolution”. These cars featured the following changes and upgrades:
- Black Cherry or Pearl White colour
- Parchment leather and suede interior
- 18-inch chromed wheels
- Revised Bilstein shocks
- Suspension cross member injected with urethane foam to improve ride quality.
A total of 2,150 of these cars were produced with 1,357 destined for the North American market.
This was the first special edition for the United Kingdom and was named after the original Mazda concept car seen in Detroit in 2000. Only 500 of these cars were produced and they featured the following.
- 228 hp 6-port 1.3-litre engine (based on the standard model)
- Exclusive Red Mica or Phantom Blue Mica colours
- Unique dark silver 18 x 8J alloy wheel
- Polished aluminium Rotary crest on the front air dam
- Dark silver bezel headlamps & sports door mirrors
- Polished aluminium side air outlet fins
- Stylish Rotary branded B-pillar trims
- Chrome exhaust surrounds and ‘Evolve’ badging
- Stone leather and Alcantara sporty seat trim
- Leather-wrapped steering wheel, gear knob and hand-brake lever.
Jointly developed with motorsports company Prodrive, the 2006 PZ RX-8 featured a number of performance and style upgrades over the standard car. It only came with a six-speed manual transmission and was based on the 228-horsepower version of the RX-8. Changes and upgrades are as follows:
- Bilstein dampers and coil springs from Eibach
- 15mm lower ride height & 60% increase in spring rate
- Win exhaust system with “Prodrive” branding
- New rear spoiler
- 18-inch OZ alloy wheels
- Prodrive and OZ branding
Altogether, Prodrive and Mazda produced 800 of these PZ RX-8s. 480 of them were produced in Brilliant Black while the other 320 were produced in Galaxy Grey.
A limited run of 100 RX-8s were produced for the Australian market in 2006. These were known as the ‘Revelation’ and they incorporated the top specification features of the RX-8. Features on the Revelation included:
- Copper Red or Brialliant Black paintwork
- Sand-coloured Alcantara seat trim
- Unique smart keyless entry and engine start system
- 9 speaker Bose sound system
- 18-inch grey spoke alloy wheels
- Stiffer anti-roll bars and foam-filled cross members
- Xenon headlights with chrome bezels
Launched in 2006, the ‘Nemesis’ was the third special edition model launched in the UK. Based on the 189 hp version of the RX-8, it was offered in a number of unique paint colours and interior trims, plus it came with an exclusive accessory package. The features are as follows:
- Copper Red Mica or Stormy Blue Mica paintwork
- Polished aluminium rotary crest and front wheel arch vents
- Exclusive badging
- Stone leather seating, aluminium scuff plates & Nemesis-embroidered floormats
Mazdaspeed M’z Tune
Launched in 2006 for the Japanese market, the Mazdaspeed M’z Tune was designed for performance at the expense of comfort. It was equipped with the following:
- Mazdaspeed bodykit: lip spoiler, sides, rear, wing
- Bilstein dampers and sport springs
- Lightweight flywheel and improved radiator
- B-spec brake pads
- Sports muffler
- Extra oil cooler
- Mazdaspeed bucket seats
- Mazdaspeed badging
A limited-edition version of the RX-8 known as the Kuro was launched in 2007 for various markets around the world. Mazda limited production to a total of 500 cars and they were all based on the 6-port 6-speed manual version of the car. The specs were as follows:
- Racing-type fully adjustable front & rear Tein suspension
- Unique Sparkling Black Mica paintwork
- 18-inch dark-silver alloy wheels & Numbered stainless steel scuff plates
- Unique stone leather interior & Bose premium audio system
- Kuro branding on the interior and exterior
40th Anniversary Limited Edition
In 2007, Mazda dropped the ‘Sports Prestige Limited’ (Shinka) model and replaced it with the 40th Anniversary Limited Edition RX-8. This car was essentially the same as the Shinka model (Bilstein dampers, etc.) but with a few other colour and interior options. It also featured 40th Anniversary Edition branding.
Second Series RX-8 (2008 – 2012)
In November 2008 Mazda made a number of changes and improvements to the RX-8. Engineers increased the rigidity of the RX-8 through the addition of structural reinforcements such as adding a trapezoidal shock tower brace and enhancing the local rigidity of the front suspension tower areas.
They also revised the rear suspension geometry for better handling and changed the gear ratio on manual cars from 4.444 to 4.777 for improved acceleration. While these changes were small, Mazda’s engineers claimed that the second-generation car was slightly faster than the previous generation and had better handling.
The RENESIS II engine fitted to 2009 model RX-8s and beyond was given a third oil injection port in each rotor housing that fed oil to the middle of the rotor facing. This made it their first all-new EMOP (Electric Metering Oil Pump) with a total of 6 lubrication injectors. A new engine oil pump was also fitted to the face-lifted RX-8.
In addition to the mechanical changes, Mazda also made a number of visual enhancements as well. These included new, more aggressive front and rear bumper designs, new front and rear headlamps, larger exhaust pipes, new five-spoke wheels and a rear spoiler on some models. Customers could choose from Sport, Grand Touring and R3 model trims for RX-8s produced from 2009 to 2012.
Special Edition Models
The R3 model launched in 2009 had a number of improvements over the standard model. It featured the following:
- Bilstein shocks
- Foam filled front crossmember to improve rigidity
- 19-inch forged aluminum-alloy wheels and high performance tyres
- Bose sound system
- Lower front bumper with splitter, lower side sills & a standard rear spoiler
- Recaro seats up front
- Keyless entry
Produced to celebrate the end of the RX-8’s production, the Spirit R was the most expensive and fastest model produced. The “Spirit R” name was based on the final edition of the RX-7, the RX-7 Spirit R. Only 1,000 of these special edition cars were produced and most of them were sold in Japan (a few were exported to countries such as New Zealand, Malaysia and Indonesia). The Spirit R was based on the 6-port version of the RX-8 and featured the following:
- Choice of 6-speed manual or 6-speed automatic with paddle shifters
- RX-8 Spirit R were bi-xenon headlamps
- 4 piston front and rear red brake calipers
- High performance Bridgestone Potenza summer tires
- 1 channel 300 watt Bose premium audio system with AudioPilot noise cancellation technology
- High-pressure fuel pump & larger radiator
- Reworked engine and electronics
- Upgraded cold air intake system with second intake port on S-DIAS system
- Upgraded oil-metering pump that supplied more oil to the rotors
- Less restricted stainless steel exhaust with 3.5 inch tips.
- Tochigi Fuji torque vectoring limited-slip differential
- Upgraded ignition system
- Bespoke track-ready suspension with Bilstein dampers and a urethane-foam-injected front suspension cross member
- Aluminium bonnet, rear doors and boot lid, along with a magnesium steering frame and a lightweight carbon fibre prop shaft
- Manual car came with red leather Spirit R Recaro bucket seats and 19-inch BBS bronze aluminium alloy wheels
- Automatic models came with 10-way adjustable power leather seats with lumbar support and 18-inch lightweight BBS dark gunmetal alloy wheels
With the improvements made, the Spirit R could accelerate from 0-100 km/h (62 mph) in as little as 5.7 seconds and could hit a top speed of around 270 km/h (170 mph). This made it the fastest factory RX-8 ever built and the most desirable.
The RX-8 Spirit R was available in Aluminium Metallic, Sparkling Black Mica, and Crystal White Pearl Mica, an exclusive colour for the Spirit R.
The End of the Mazda RX-8
Sales of the RX-8 ended in Europe in 2010 after the car failed to meet the region’s strict emissions standards. Production and sales continued in Japan and other regions until 2012. Mazda produced a total of 192,094 RX-8s since 2003 at their Ujina, Hiroshima plant. Unfortunately, Mazda did not have a successor to follow the RX-8 and the company retired the rotary engine. However, there have been talks of a RX-9 launching at some point in the future, but at this stage it is just rumours.
Mazda RX-8 Specifications
Year of production
2003 – 2012
Front mid-engined, rear-wheel drive
RENESIS (Wankel rotary)
4 or 6-port
189 – 237
6-speed automatic (paddle shift)
1,309 – 1,384kg
233 – 270 km/h (145 – 168 mph)
0 – 100 km/h (62 mph)
5.7 – 6.4 seconds
Mazda RX-8 Buying Guide
Now that we have covered the history and the specifications of the Mazda RX-8, let’s take a look at buying one. In this section of the article we are going to be covering specific problems with the RX-8 and things to watch out for. At the end of the guide we have more general car buying advice and information on how to import a Mazda RX-8 from Japan.
It is important to inspect any RX-8 yourself or get a reliable third party to do so for you (if it is not possible for you to inspect it). The Mazda RX-8 has a bit of a reputation for causing trouble, especially if they have been maintained poorly or driven incorrectly. A good one should provide you with plenty of miles of motoring fun, but a bad one can drain your wallet quickly.
Always try to get a viewing in the morning when the engine is cold if possible. Warm engines can hide a number of problems, so be careful of RX-8s that are pre-warmed. Additionally, avoid inspecting a car when it is wet as water can cover up issues with the paintwork and body.
Why Do RX-8s Have Such a Bad Reputation for Reliability?
The rotary engine fitted to the RX-8 gets a bad rap, both justifiably and unjustifiably. One of the reasons for this bad reputation is due to the earlier models (2003 – 2005) and how their rotary engines failed worryingly early.
The ECU on these early engines wasn’t injecting enough oil which lead to premature wear on components or total engine failure. A common sign of this problem was loss of power or misfiring. Many owners tried to solve this problem by changing the spark plugs and when that didn’t happen, they would take it back to the dealer. When the dealer couldn’t work out the problem, they would replace the engine and send the customer on their way.
It wasn’t until years later that dealers started to realise that it was the Ignition Coils causing the problems. They would fail around 50,000 km (30,000 miles) causing the problems that owners were experiencing. It is believed that a large portion of the original engine failures were caused by this issue and were replaced unnecessarily.
In addition to this, Mazda made the issue worse by rebuilding the ‘dead’ engines. There is nothing wrong with rebuilding engines, but the quality control at the manufacturing plant were Mazda did the work was exceedingly poor.
The result of this was that many of the rebuilt engines were worse than the original factory ones. These engines were known as Reman (remanufactured) engines and they suffered from numerous problems, including the one that they were originally put in to fix (ignition coils). This means that a customer may have had a perfectly good engine in their RX-8, but it was replaced with a dog of an engine due to a misdiagnosis of the issue.
How Many RX-8s Have Had Their Engines Replaced?
It is not known what the exact number of replacements is, but it is believed that around 50% of RX-8s have had at least one engine replacement in their lifespan.
The reason for this high number is because even if you remove the problem with the ECU/ignition coils and the poor quality Reman engines, there are still a few major problems that can hurt the lifespan of a RX-8’s engine.
Most RX-8s get a second engine within 160,000 km (100,000 miles), which is fairly regular. However, the main reason for this is not what the general pubic likes to believe.
What About Newer RX-8s?
With the introduction of the second series RX-8 in 2009 Mazda introduced a number of subtle yet significant changes that improved reliability dramatically. The most import of these changes was an increase in oil pressure to RX-7 ranges (they had dropped it for 2004 – 2008 RX-8s). Mazda also reintroduced the centre oil injector which was also removed from 2004 – 2008 cars.
While these changes don’t make later RX-8s immune to engine failures, it did help to reduce wear-related failures by quite a bit.
What Are the Main Causes of Engine Failure in an RX-8?
Below we have listed the main causes of failure for an RX-8’s rotary engine:
- Excessive carbon build-up accelerating seal wear – causes compression loss (automatic RX-8s are more prone to this problem).
- Excessive carbon build-up unseating the apex seals – causes compression loss (automatic RX-8s are more prone to this problem).
- Excessive heat build-up warping the housings – prevents the apex seals from sealing, causing a loss of compression (older RX-8s that have not had their cooling system overhauled are more likely to suffer from this problem).
- Excessive exhaust temperatures overheating the side seal springs – warps the springs until the side seal pops out of its position. It then clips the exhaust port and shatters, throwing shrapnel through the engine (RX-8s that are turbocharged, supercharged or those that have seen significant track use are more likely to have engine failures caused by this).
- Fuel pump failure or fuel starvation caused by high lateral G left turns – creates a lean spike that causes detonation and shatters the seals (older RX-8s that haven’t had a fuel pump replacement or more likely to suffer from this)
- Cat Failure (even more common than engine failure) – this causes heat and pressure build-up that over stresses the seals and reduces the oil’s viscosity, leading to various issues (usually effects new owners who don’t know how to replace their ignition).
- Clogged oil injection lines that prevent oil from being injected – this leads to excessive apex seal wear and side seal overheating. Compression loss and/or engine failure will result if this problem is not attended to (this is quite a common problem on cars that have not had their oil changed regularly.
- Poor quality Reman engines with bad/low compression – the above problems will occur quicker/earlier on these poor quality engines (Reman engines did improve over the course of the RX-8’s production, but bad ones did slip through the net).
These are the main causes of engine failure in an RX-8, but there are some less common ones as well. If possible engine failure makes you uncomfortable, then purchasing an RX-8 probably isn’t for you.
Inspecting & Condition
In 2019 RX-8s (especially early model ones) can be purchased quite cheap. This means that a lot of them have got into the hands of people who don’t maintain them properly or can’t afford to do so. Along with the reasons we discussed above, the owners who maintain their cars poorly also add to the RX-8’s poor reputation for reliability.
A well-maintained RX-8 that has been driven properly can provide many miles of problem free motoring. It is important that you take your time when you are inspecting any RX-8, and don’t purchase one that has been maintained poorly.
Vin Location on RX-8s
We always recommend that you check the VIN (Vehicle Identification Number) of any RX-8 you look at. Checking the Vehicle Identification Number on a VIN checkup website can tell you a lot about the history of a car (if it has been written off, etc.). You should be able to find the VIN at the back of the engine bay.
To start your inspection of an RX-8’s engine, open the bonnet and take a good general look at the engine bay – Is there anything that sticks out? Does it look well maintained and clean? Is it stock or modified?
Once you have done this move on to checking the fluid levels to see if they are at the correct level. Fluid levels that are incorrect can cause premature wear to a vehicle’s components and are a sign of poor maintenance (this is especially true for the RX-8’s rotary engine).
When to Change the Oil & Oil Filter?
Both the engine oil and oil filter should be changed at or before the recommended service interval. This is because old oil can breakdown overtime and become diluted in the presence of contaminates. Below we have listed when the oil and oil filter should be replaced:
Engine oil – The RX-8 manual recommends that the oil be changed at 12,000 km (7,500 miles) for normal use and 8,000 km (5,000 miles) for heavy use. However, many owners recommend changing it much earlier at around 5,000 km (3,000 miles) or every 6 months – 12,000 km is not recommended!
It is recommended that you use something like Castrol GTX 5W-30. However, this can change depending on where you live and the temperatures that the car will experience (eg. 10W-40, 5W-20 and more may be recommended). Typically, heavier weight oils (higher numbers) are better for hotter environments and thinner oils are better for cold.
When it comes to non-synthetic (dino) vs synthetic there really isn’t much difference for the RX-8. Mazda does recommend non-synthetic, but it is not required. Plenty of owners run their RX-8s on synthetic oil. The most important thing is to keep it topped up and do regular changes.
Oil filter – Most owners recommend that you change the oil filter with every second oil change. Some owners will change it with every oil change to be safe (sign of a good owner). The oil filter should be changed with a genuine Mazda oil filter (part number B6Y1-14-302A), however there are some other alternatives that can be used (be careful with later models however). Second generation RX-8s should use Mazda’s oil filter with a part number of N3R1-14-302 (thanks to Randy for letting us know).
If you notice any metallic particles or other contaminates in the engine oil, move onto another RX-8. Black oil is fine and just indicates that it is probably time for a change.
I’ve Heard That the RX-8 Burns A Lot of Oil, Is This True?
The answer is yes, the RX-8 does burn a lot of oil, however, this is not actually a problem and here is why.
RX-8s burn oil intentionally to keep the seals/engine healthy. The engine seals are located inside the combustion chamber and the only way to lubricate them is to inject oil (or have oil in the fuel, known as premix). This oil then gets burned under combustion, which means that new oil needs to be injected to keep the process going.
On average an RX-8 should burn around a quart (just under a litre) of oil every 1,600 km (1,000 miles). If your RX-8 does not burn anywhere near this much oil, then there is a problem. Insufficient oil burn means that an engine will not last long.
During an inspection, remember to ask the owner about this. If the owner claims that the car doesn’t burn much oil, they either don’t know what they are talking about or there is a problem and you should move onto another RX-8.
If the RX-8 you are looking at burns more oil than what we stated above it could be down to a number of reasons:
- Oil injection has been increased – This isn’t usually an issue and you will typically see oil burn of about one quart every 800 – 1,400 km (500 – 1000 miles).
- Oil control ring failure – Oil will leak into the housing and the burn rate will be about 300 – 600 km (200 – 300 miles). Requires an engine rebuild to fix. This can be left but you will get through a lot of oil, the plugs will get fouled faster and the coils won’t last as long. Additionally, if you let the oil get too low it will destroy the engine.
- Severe vacuum problem – The engine actively sucks oil into the intake. Burn rate is around 300 – 600 km (200 – 300 miles).
It is incredibly important that you try and keep the oil filled above the ½ full mark. If the oil light comes on it means that the oil level is already critically low (check for this during an inspection and ask the owner if the oil light has ever come on).
Overfilling the oil is also bad, so check for this as well. If there is too much oil it can spill over into the intake and gum up the intake valving. This can be costly to repair!
What About Flooding?
If the RX-8 you are inspecting does not start it may have a flooded engine. Flooding happens when there is too much fuel in the combustion chamber. This really only occurs when the driver attempts to start the car, but the engine doesn’t start immediately.
The ECU pumps fuel into the engine while it is cranking, and if the engine does not start up quickly enough the fuel soaks the spark plugs and fills the housing. This keeps the ignition from firing, so the car can’t start.
Flooding is only a concern if the car has a weak ignition system, failing compression, a failing battery, and/or a failing starter. Most floods can be traced to the following:
- Plug Wire/Wires
- Spark Plug/Plugs
- Engine Compression
How to Fix a Flooded Engine?
There are a variety of ways to fix a flooded engine, but the first way you should try is to use Mazda’s built in ECU tool.
To do this, connect another running car to the RX-8’s battery with jumper cables to keep the battery from dying. Following this, press the throttle pedal to the floor (this signals the ECU to stop all fuel injection while cranking) and crank in 5-10 second intervals, waiting the same amount of time between each to let the starter motor cool down.
Repeat this process around ten times, then take your foot of the throttle pedal and try to start the car normally. If it won’t start, try the process again.
For those still having problems you can do a quick google search and pick one of the other DIY de-flooding methods. Do not mix methods as this can cause its own set of problems!
How to Prevent Flooding
It is important to stay on top of maintenance to prevent this problem from occurring. Make sure that all the coils, plugs and wires are replaced every 50,000 km (30,000 miles) or sooner. Check the service history and ask the owner to see if this work has been done regularly. In some occasions, these parts have failed much earlier, so be careful!
Another tip is to make sure that you do not start the engine when it is cold. This is because the ECU dumps more fuel into the engine when it is cold to help warm it up. The ECU reduces the amount of fuel it injects once the car is up to the correct operating temperature.
This extra fuel can make it much harder to start, which can cause flooding if the plugs, starter, battery, etc. are bad. RX-8’s with healthy ignition systems should be able to overcome this issue.
If the owner turns the RX-8 you are inspecting off when it is cold it is a sign that they do not know how to look after the car properly!
Checking the Spark Plugs & Ignition System
If possible, try to get a look at the spark plugs and spark plug wires to see if they are in good condition. The appearance of spark plugs can tell you a lot of information about an engine and how it is running. We recommend that you check out this spark plug analysis guide.
It is recommended that you change the plugs every 32,000 – 50,000 km (20,000 – 53,000miles).
You should always go with OEM plugs unless you have a turbocharged or supercharged RX-8. You should go with the following:
NGK brand, two each of:
RE9B-T <- (trailing / top plugs)
RE7C-L <- (leading / lower plugs)
A healthy ignition system is one of the most overlooked yet important parts of RX-8 ownership. This not only includes the spark plugs and spark plug wires, but also the ignition coils. A failing ignition system can not only cause problems like we discussed above but it can also lead to significant power loss.
When coils fail, they don’t suddenly shut off. They start producing weaker pulses that are scattered among stronger ones. Weaker pulses then become more and more frequent and eventually pulses start dropping altogether.
The result of this is insufficient fuel burning and not full use of the air being pulled into the engine. Unburnt fuel and air then gets dumped into the exhaust, where it ignites in the presence of heat. This can then saturate the catalytic converter causing it to fail. Driving a RX-8 without a catalytic converter can damage the engine.
Why Do RX-8 Coils Fail So Easily
This mainly comes down to the quality of the coils that Mazda used in the RX-8’s engine. On the RX-7, many owners complained about the cost of the coils, so Mazda decided to use cheaper ones for the RX-8. Compared to RX-7 coils, the ones used in the RX-8 need to be changed much more frequently.
Another reason why they fail much earlier than on a traditional piston engine is because of much they fire. On a piston engine the coils fire every other rotation whereas on a rotary they fire every rotation. Add to the fact that rotary engines tend to run at a higher rpms and you have a recipe for coil wear and failure.
What Coils Should I Buy & Where Can You Buy Them?
There are a number of different coil options and upgrades that you can purchase. We have listed these below.
- BWD/Intermotor Coils – These are essentially just OEM coils but rebranded. They are probably the cheapest option and expect them to last around 32,000 – 50,000 km (20,000 – 30,000miles)
- Genuine OEM Coils – You can get original OEM coils from Mazmart/Mazda. These will probably last longer than the rebranded ones as they are the latest revision.
- Coils From eBay, etc. – You can purchase coils from websites such as eBay, but there is a much higher risk that you will receive counterfeit, dead on arrival or mislabelled units. Watch out for “Motor King” coils as they are ineffective and anything labelled as genuine Mazda are probably fake. If you do want to purchase coils off a website like eBay make sure you check the sellers feedback and watch out for any deals that seem too good to be true
- BHR Ignition Coil Upgrade – This is an upgrade for the RX-8 and eliminates the need to continue replacing coils periodically, as well as delivering a significantly stronger spark for minor mileage and power gains. While this kit includes the wires it does not include the spark plugs
Checking the Cooling
Probably the biggest cause of engine failures in RX-8s today is due to bad or failing cooling systems. Many RX-8 owners do not maintain their cars properly and the cooling systems on these vehicles are usually well past their normal operating lifetime.
The rotary engine in the RX-8 produces a lot of heat and this heat must be removed somehow. This is where the cooling system comes in. The major components in the cooling system include the following:
- Radiator – removes heat from the water/coolant
- Thermostat – sends water/coolant that is hotter than the target temperature to the radiator to be cooled
- Water Pump – belt that is driven from the e-shaft pully. Pushes water/coolant through the engine
- Overflow or Expansion bottle – removes air from the system and provides a filling point
- Coolant Lines – hoses that allow water/coolant to remain contained as it moves through the engine/cooling system
If any of the components above fail it can possibly lead to an engine loss. The coolant seals on an RX-8 are only really trustworthy to a coolant system temperature of about 104 degrees Celsius (104F). Once you get beyond this point there is a much greater risk of one of the coolant seals failing.
Temperatures exceeding around 115C (240F ) can warp the rotor housings, which is an even bigger problem. This problem is exasperated by the fact that the factory coolant temperature gauge (the one in the instrument cluster) doesn’t start moving from the centre point until 113C – 115C (235F-240F)
If you are inspecting an RX-8 and you notice the temperature gauge moving past the centre mark you should move onto another one. While it doesn’t necessarily mean that there is engine damage, it is a serious problem. if the temperature gauge moves all the way to the right and some serious repair bills will probably result.
RX-8s that overheat when stopped or at slow speeds may have a problem with fan airflow. If the fans are running correctly it may be a sign that the radiator is blocked. If this happens during a test drive, turn off the car and see if you can find something obstructing the fans or radiator.
Using an OBD2 Scanner To Find the Correct Temperature
The best way to find the operating temperature of an RX-8’s rotary engine is to use an OBD2 scanner. OBD2 is an emissions compliance standard that has existed within the United States since 1996, and all cars sold in the country since then have had to comply with it. Most cars you see on the road that have been produced since then are OBD2 compliant and have an available OBD2 port.
An OBD2 scanner can give you lots of information about a cars engine and is definitely worth purchasing. We have a complete guide on the best OBD2 scanners here.
How to Prevent a Cooling System Failure
The best way to prevent a cooling system failure and resultant loss of engine is to make sure that proper maintenance is conducted. If you are not using Mazda’s FL-22 coolant you need to flush the system every year. Mazda claims that their FL-22 fluid is good for up to five years, but many owners recommended changing it every two years. Ask the owner about this to see if they have done regular coolant changes/flushes.
The thermostat and coolant bottle are common failure points. You can upgrade the thermostat to give the cooling system a bit more headroom, but don’t go lower than 77C (170F) otherwise you can cause a whole host of issues (power loss, increased fuel consumption, CEL, etc.).
Check the service history and ask the owner to see if the radiator has ever been replaced. If not, make sure it is in good condition and not overly clogged. If the RX-8 you are looking at has a Mishimoto radiator, be careful. Mishimoto radiators are more expensive and inferior to OEM ones.
The coolant lines should have been replaced if the radiator has. While it is not necessary to replace the lines detritus can build up in them which will reduce cooling performance. Silicone lines are more expensive than rubber ones. During an inspection make sure you check the coolant lines for any damage, leaks or other issues.
Water pumps eventually fail, so check the service history to see if it has already been replaced. If the water pump has not been replaced and the car has seen a lot of miles you may want to consider replacing it.
Exhaust & Catalytic Converter Issues
Get under the car and inspect as much of the exhaust system as you can. While there are not any factory problems with the exhaust system, make sure it is in good condition. We have listed some things to watch out for below:
- Black sooty stains – indicate a leak which may be expensive to fix
- Corrosion – Minor corrosion is probably fine, but excessive amounts of rust is a major problem.
- Cracks or accident damage –pretty self-explanatory and can be expensive to repair
- Dodgy repairs – Watch out for any bad repairs as this can be a nightmare to put right and is a sign of a poorly maintained car.
It is quite common for the catalytic converter to fail. This is because the heat and emissions produced by an RX-8’s rotary engine are not kind to them. Additionally, most of the encountered failures on RX-8s cause misfires which destroy a catalytic converter quickly. A clogged/blocked catalytic converter is dangerous to the engine, the car and possibly even your life!
Discoloured or Foamy Substance on the Dipstick
If you notice a milky like substance on the dipstick, don’t worry, it’s not a head gasket failure. Rotary engines don’t have head gaskets and this substance does not affect engine performance or any other functions of the vehicle.
During cold weather, moisture contained in blow-by gases (exhaust, water vapour, oil, fuel) is cooled by the intermediate housing wall and condenses due to the difference in temperature. A chemical reaction then occurs between the moisture and as a result a milky/foamy fluid will develop in the intermediate housing. This milky substance should dissipate as the engine warms up to the correct operating temperature.
The milky fluid does not affect the quality of the engine and therefore it does not negatively impact performance. Mazda has confirmed that the amount of moisture in the oil is well within the acceptable standard for motor oils commonly found on the market.
While this substance is harmless, we recommend that you check that the coolant reservoir is full and that there is no sign of engine coolant leakage.
Mazda dealers/service centres do offer an oil level gauge plastic insert that has been developed to keep the milky substance off the dipstick (however, this is only a cosmetic fix and the substance will still be in the engine).
Smoke or Vapour Coming from the Exhaust
It is important to check for any smoke or vapour coming out of the exhaust both on engine start-up and while the vehicle is running. Expect to see some vapour caused by condensation in the exhaust system. If you notice excessive amounts of vapour or smoke, move onto another RX-8. Here are what the different smoke colours indicate:
Blue Smoke – means burning oil and there are 3 main ways that it can get into the engine.
- Too much oil in the gas tank (would generally have power problems)
- Oil overfilling into the intake (this is bad and there would be all sorts of unstable and unpredictable problems)
- Oil control ring failure (no apparent difference other than the smoke and higher oil consumption, usually smoke appears when you let off the throttle, as the vacuum is when oil gets pulled in, and off throttle means no fuel so only oil is getting burned)
The first two problems are easy to verify and fix. Make sure you don’t put oil in the tank next time you fill it up and if there is oil in there run it really low to burn out as much as possible. Oil in the fuel/gas is normally fine and in some cases recommended, but it needs to be in the right quantities.
If you suspect that there is oil in the intake you will need to pull apart the intake track to see if there is any oil residue or clumps of it. Oil in the intake messes with the intake valving and MAF, and can cause all sorts of issues.
If both of those are fine, or don’t fix the problem, then it points to an oil control ring failure. Check the car’s service history to see if any work has ever been done on the oil control rings.
It is possible to drive indefinitely on a rotary with one of more failed oil control rings as long as it is topped up with oil. However, if you let it go low it can lead to one of the many engine failures we discussed earlier.
White Smoke – A few puffs of white smoke/steam is usually caused by condensation in the exhaust. Lots of white smoke is a sign that the cooling system has failed and coolant is leaking into the combustion chamber.
White smoke is definitely bad for rotary engined cars as the cooling system is incredibly important. If you notice lots of white smoke and it smells slightly sweet, you should move onto another RX-8.
Black Smoke – A sign that the car is running too rich (burning too much fuel). The first thing you should do is to check the air intake components to make sure they are in good condition.
Start Up & Idle Speed
During an inspection, get the owner/seller of the car to start it for you. There are two reasons for this:
- To see if any smoke comes out the exhaust.
- To see if the owner revs the car hard on start-up. If they do, move onto another RX-8.
Keep an ear out for any strange noises or signs that the vehicle is struggling to start. If the car doesn’t start or struggles to start it may have one of the issues we listed earlier in this guide. Any loud bangs or knocks should make you walk away.
The idle speed should be around the 750 – 900 rpm mark, but this will depend on a number of factors. Remember to turn on all the electronics to make sure the car doesn’t stall. When you do this expect to see a slight increase in the idle speed. Additionally, you may see the idle speed drop after you rev an RX-8. Below we have attached an image of the standard idle speeds from the service manual.
Watch Out for a Weak Starter
Models produced until early 2005 were fitted with rather weak starters. From mid-2005 onwards Mazda fitted a much stronger starter that lasts a lot longer. Mazda offered to upgrade the early cars with the new starter for free, but it was not a recall. If you are looking at one of these early RX-8s, check to see if the starter was replaced.
Misfires & CEL
Misfires are usually caused by a problem with the ignition system (failing coils, plugs, etc.). However, they can also be caused by a number of other more serious issues as well such as a failed catalytic converter, vacuum leak, engine failure and more.
The CEL (Check Engine Light or MIL) is a light on the dashboard that comes on when the ECU detects something wrong. It won’t tell you the exact problem and just indicates that there is a problem.
A flashing Check Engine Light indicates that the ECU is detecting a misfire. There are no other conditions that will trigger a flashing CEL. Misfires need to be addressed quickly as they are a sign that more components failures are on their way.
If the CEL comes on there are a few different ways to clear it:
- Disconnect the battery without reading the code to see what is wrong. This also clears your fuel trims, audio head unit presets, DSC/TCS learned parameters. Note, your car may idle for the next few drive cycles
- Visit a car-parts store where they should be able to read the code for you (usually free, but depending on where you live you may have to pay). Once they have read the code they will be able to clear it for you
- Buy a code reader for less than a diagnostics fee at a shop, read and clear it yourself, and read all future codes on all your cars for free
- Buy an OBD2 scanner and pair it with your mobile device – see here for more
- Go to a shop and pay for them to get the code
- Visit a dealer and pay even more to get them to read the code and clear the CEL.
You can find out more about what the CEL codes mean here. Note, some failures will produce more than one code.
Rattles from the Glovebox Area
A rattling sound that appears to be coming from the glovebox area is usually caused by Secondary Shutter Valve (SSC) failure. This can result in power loss and is typically caused by the valve getting over carboned from oil burping or excessive oil vapours in the intake. Dealers will charge an arm and a leg to fix this issue, but fortunately it is not that common. DIY methods are possible to fix this issue (read here).
The Motor Mounts Can Fail
Failing motor mounts can cause the car to shake more, especially at ideal. It isn’t actually the engine attachment points that fail, but the vibration dampeners. Fixing this problem immediately isn’t vital but it should be done at some point (some owners choose to live with it).
Should I Do a Compression Test?
Yes, we absolutely recommend that you get a compression test done on any RX-8 before purchase. To test an RX-8’s compression you cannot use a traditional analogue compression tester. A typically analogue compression tester simply plugs into a spark plug port and as the engine cranks, the needle moves and you can easily see the compression reading.
The reason you can read the compression easily is because you are testing one spark plug and one cylinder, which gives a single compression reading. On the RX-8 you will be testing one spark plug with three rotor cavities, which will give you three compression numbers per revolution.
There is no easy way for a simple analogue tester to record the compression for each face of the rotor independently as it spins (However there is a complicated method which you can read here).
What this means is that you will have to take the RX-8 you are thinking of buying to a Mazda dealer or a specialist who can do a compression test on a rotary engine. If the owner/seller does not want you to do a compression test than you should move onto another RX-8!
What Do the Compression Numbers Mean?
The Mazda specialist or dealer should be able to tell you if the compression is good, but we have also put together some information for you below.
Results from the compression test should look something like this:
|Rotor 1 (250 rpm)||Rotor 2 (250 rpm)|
The three readings from each rotor are your compression scores (one for each face of the rotor in the engine). There should be six numbers in total and at least one rpm number. If you don’t have this it will be difficult to get an accurate picture of the car’s compression.
Depending on where you get the compression test done the results may be in a different unit (psi, etc.). Additionally, it is vital to get the rpm value as rotary compression changes with engine speed, especially at lower revs.
Doing a compression test can also help determine the condition of the starter as the engine is spun by it.
Here is a general guideline for compression readings from a Mazda RX-8.
8.50 and above – Compression scores this high are a rarity and are a sign of excellent engine health. However, scores this high can also mean that there is/has been excessive amounts of oil in the housing.
8.0 – 8.4 – Engines that produce a reading like this are in very good condition and should last a long time if they are maintained properly.
7.5 – 7.9 – This is an acceptable level of compression and you will find that most engines from Mazda seem to be in this range after the break-in period. If you stay on top of maintenance, engines with this compression should last you around 65,000 – 100,000 km (40,000 – 60,000 miles) or possibly even longer.
7.0 – 7.4 – This is where things start to go downhill. While engines with this level of compression will still have some life left in them, a replacement may be needed in the near future (or it may still go on for a long time). Compression loss will start to speed up at this point as combustion gases will eat away at the seals.
6.5 – 6.9 – The engine is officially classed as failing and won’t have much life left in it. Compression loss will continue to increase due to combustion gases eating the seals.
6.0 – 6.4 – A reading in this range indicates that the engine is failing significantly, and death is right around the corner. The engine will be extremely prone to flooding, even with a top-notch ignition system. When driving a car with this sort of compression you should notice power loss (at low rpms especially), idling problems and it will have difficulty starting when hot.
5.5 – 5.9 – Much the same as above, but you will have even more problems starting and running the car. Expect to replace/rebuild the engine in the very near future.
5.0 – 5.4 – A car with this sort of compression will be almost impossible to use as a daily driver. Starting it will be a nightmare and expect to have a wallet wounding experience.
5.0 and Below – An engine with this sort of compression is pretty much dead and needs to be replaced.
Things That Can Affect a Compression Test
If the test was carried out incorrectly it can affect the numbers that are produced. Additionally, if there is excessive amounts of oil in the housing the results will be higher, and if the test was not done at 250 rpm and at sea level the compression numbers will have to be normalised. This can be done here.
If you asked us, we would never buy an RX-8 with a non-stock engine. There are more engine swaps started than finished and very few of those are completed to a high standard. Many owners who start an engine swap run out of money or finish the project but find that the car has a whole host of issues. They then try to palm their problem off to another to claw back some of the money they lost.
If you are still keen on an engined swapped RX-8, make sure all the work has been carried out correctly. Get a specialist to check out the work and inspect all of the receipts/paperwork to see who did the swap. If they are some no name you are better off moving onto another RX-8.
What About Turbocharged or Supercharged RX-8s?
While there are some small modifications you can do to get more power out of a RX-8, if you really want to increase performance you are going to have to supercharge or turbocharge the engine. However, turbocharging or supercharging an RX-8’s engine is not for the fainthearted.
No single forced induction kit on the market is perfect and they all have their problems. Expect to spend a significant amount of money to get one of these kits working.
Buying a Supercharged or Turbocharged RX-8
If you are looking at purchasing an RX-8 with a forced induction kit we would advise caution. Like engine swaps, most of the people who do these modifications to their RX-8s run out of money before they get them working. The owner/seller may be trying to offload their problem onto you, so be cautious.
Any modifications should be carried out by somebody competent like a Mazda specialist and you should always get these cars inspected before purchasing them.
You shouldn’t find too many issues when it comes to the transmission in an RX-8. However, problems can start to appear with regular spirited driving or if the car has been used on a track. Additionally, if the RX-8 you are looking at has some power modifications the gearbox will wear faster.
During a test drive, listen out for any strange grinding or whining sounds from the transmission. Whining can indicate a whole host of issues from incorrect transmission fluid to bearings that have been damaged from continuous high rpm shifting.
On manual cars, make sure you shift through all the gears at both low and high engine speeds to check for any synchro wear, graunching, etc. If the car has worn synchros it is a sign that it may have been thrashed.
For automatic cars, go through all the different positions/gears while the car is stationary and while it is moving. Loud clunks, knocks or whining should set off alarm bells in your head and the car probably isn’t worth your time.
Automatic cars are probably less likely to have transmission wear as they are usually not thrashed as hard. Additionally, there is no clutch to worry about.
Remember to check that the transmission and differential fluid has been changed at the required interval or before (50,000 km/30,000 miles)
The clutch fluid should be checked every 16,000 km (10,000 miles) and topped up with DOT 3, 4 or 5.1. A worn clutch on a Mazda RX-8 can result in an expensive bill, so make sure it is in good condition. Here are some ways to test a clutch’s health:
Clutch Engagement – Put the RX-8 you are test driving into gear on a level surface and let the clutch out slowly. It should engage around 7 to 10 cm (2.5 to 4 inches) from the floor. If it engages immediately or near the end of the pedal’s travel, there is a problem.
Clutch Slippage – Shift into a gear that is too high for the speed you are going and then plant your foot on the throttle. If the engine speed jumps but there is no acceleration the clutch is slipping. Clutch slippage can be caused by the following:
- Worn clutch
- Clutch covered in oil
- Clutch cable is too tight and is not releasing properly
Clutch Drag – Put the RX-8 on a level surface with the clutch pedal pressed to the floor (when you are stationary) and rev the car hard. If the cars moves then the clutch is not disengaging when you shift and parts will wear prematurely.
Juddering or a stiff pedal also indicate that the clutch needs to be replaced. The life of a clutch will depend on how it has been treated and how the car has been driven. They can last a long time or wear quickly if the car has seen repeated high rpm shifting.
RX-8s Have a Weak Clutch Pedal Assembly
The clutch pedal assembly on the RX-8 is particularly weak and overtime the pivot points will wear through the mounting points. This will lead to a failure in the assembly.
If you hear a squeaking sound from the clutch as it is depressed and released the issue is getting worse. A new assembly will fix this issue until it breaks as well. After market options are available or you could get the original assembly rewelded.
Automatic vs Manual RX-8s
If you are looking for more engaging driving characteristics and can drive stick, we recommend that you go for a manual RX-8. The manual versions of the RX-8 are quicker than the automatic ones, even though they produce around the same amount of torque.
The reason for the increase in speed is because manual RX-8s have a much higher redline, which means they can keep accelerating for longer before a gear change is needed. However, you won’t really feel the difference in speed as the difference is so small.
What About Paddle Shift Automatic RX-8s
Some models of the RX-8 came with paddle shifters or more specifically buttons that trigger up and down shifts. The transmission and shift speed is still the same as the normal automatic, the only difference is that you can make it go up and down through the gears. However, the ECU can still decide to ignore your shift change, or it can make one itself.
While you may hear some people call the paddle shift transmission on an RX-8 “Tiptronic”, it really isn’t. Tiptronic is a brand name of Porsche transmissions that were not only used by them but also licensed to other manufacturers. The RX-8’s paddle shift transmission is Mazda’s own, so don’t call it a Tiptronic.
Personally, we wouldn’t purchase an RX-8 with a paddle shift transmission and would instead go for a manual model.
Body and Exterior on a Mazda RX-8
Bodywork problems can be an even bigger problem than engine issues, so always inspect the vehicle closely for the following.
While rust isn’t nearly as big a problem on these cars as some older sports cars, we always recommend that you check for it. Rust is more likely to occur on RX-8s that have lived in countries that salt their roads, cars that have lived by the sea, or those that have been stored outside for lengthy periods of time. Here are some places you may find rust/corrosion on an RX-8:
- Sills (especially where the door meets the front wing)
- Wheel arches
- Around the windows/windscreen
- Under the bonnet and in the boot/bootlid (lift up the carpets in the boot)
- Centre of the alloys, underneath the plastic Mazda badge
Note: Some early RX-8s (2003 to around 2006) were made from a bad batch of steel, which resulted in excessive amounts of rust on both the inside and outside (especially around the bootlid). Most of these were repaired under warranty but a few are still lurking out there in the wild.
It is important to not only check the car for present rust, but also for past rust. Look for any areas where rust may have been repaired in the past (inconsistencies in the paint, non-standard parts, etc.). Additionally, check the service history and ask the owner about any past rust problems (remember that not all owners will tell you the truth).
Use a magnet on steel sections of the car or a coating gauge thickness tool such as this one to find any areas that may have been repaired.
Accident Damage on a Mazda RX-8
The Mazda RX-8 encourages enthusiastic driving (especially the manual version) and many of them have been in contact with things they shouldn’t have been. Ask the owner/seller about any past accident damage, but don’t always trust their word. Here are some things to watch out for.
- Misaligned panels or large panel gaps– Make sure the bonnet fits correctly and the gaps on either side are even. Look at the doors, tailgate and around the lights. If the panels are uneven it could suggest an accident has occurred.
- Doors that drop or don’t close properly – If the doors drop or they don’t open/close properly the RX-8 you are looing at has problems.
- Inconsistencies such as waving, rippling or different coloured panels– This is a good indication of crash damage or rust repair.
- If the bonnet/hood looks like it is popped when it is not– This is usually a sign that the vehicle has been in an accident and that the owner is careless. This problem can be fixed but can be a nightmare to get right.
- Bent or broken parts underneath the car –Make sure everything is straight and check for any parts that may have been replaced. Take a good look at all of the suspension, steering and exhaust components for damage.
- Rust in strange locations –indicates that the RX-8 you are looking at has been in an accident or has some other problem.
- Paint runs or overspray –This could be a factory issue or a sign of a poor repair.
- Missing badges –can be due to repair work (body shop couldn’t find replacements) or a number of other things (stolen, etc.)
Some models such as the Spirit R came with aluminium body panels (bonnet, boot, etc.). If these have been damaged they are expensive to replace, so check everything thoroughly. Use any damage to get a discount on the vehicle. If the damage is too great walk away from the RX-8.
Water in the Taillights
This primarily affects models up to 2005, but can be seen across all years, including Series 2 RX-8s. It is caused by a failing taillight gasket that lets moisture into the taillight lens. An improved gasket from Mazda dealers/specialists can help, but doesn’t solve the problem completely. Aftermarket and DIY options are available. A last resort is to drill a small hole in the taillight, but this isn’t recommended.
Suspension and Steering
Make sure you physically inspect as much of the suspension and steering components as possible. If they look worn, damaged or corroded they will need to be replaced at some point. Replacing suspension components can be expensive so make sure they are in good condition.
Worn suspension and steering components will also ruin the handling and driving characteristics of an RX-8. Here are some things to watch out for:
- Dipping and swerving when the brakes are applied
- Excessive Rear-end squat during acceleration
- Tipping during turns
- Instability at high speeds
- Excessive vibration coming through the steering wheel
- Delayed or longer stopping distances
- Uneven tyre wear
- Excessive tyre bounce after hitting a bump
- Leaking fluid on the exterior of the shock/strut
- Knocking or creaking sounds during a test drive (remember to drive in a tight figure 8)
Problems with the Power Steering
The coolant overflow tube can dump liquid onto the power steering connectors (the main power and torque sensor connections). This problem was missed by Mazda’s quality control team and can cause various power steering problems, including complete failure.
Additionally, dust, debris, salt and more can interfere with the grease on the u-joint in the steering shaft, causing rack failure and control module failure.
It is simple enough to clean/replace the power steering connectors and reapply the grease to the u-joint. If it is the control module you have a big problem as this is expensive to replace.
Most power steering problems were addressed by Mazda dealers, but there are still a few problem cars lurking out there. Cleaning the power steering connectors and fitting a longer overflow tube will prevent these issues from occurring (for the most part).
If the RX-8 you are test driving does not drive straight without you correcting the wheel, the wheel alignment is probably out or it may have been in an accident. Check with owner/seller to see when the wheel alignment was last done.
Aftermarket Suspension Components
Aftermarket suspension components are available for the RX-8, but some modification is required to fit these set-ups. Avoid any RX-8 with cheap no-name suspension components as these could be trouble down the line. Additionally, if you need to replace aftermarket suspension it may be expensive to do so.
The RX-8 comes with exceptional brakes from the factory, so if they feel weak or spongy there is a problem. Remember to take a look at the brakes and check for the following:
- Pad life
- Pitted, scored or grooved discs
- Any leaks in the brake lines (get a helper to press on the brake pedal while you inspect the lines)
Replacing the calipers and/or discs can be expensive depending on where you live in the world. If anything needs to be replaced, try to get a discount on the vehicle if you intend to purchase it.
During a Test Drive
On a test drive make sure you test the brakes both under light and hard braking conditions. If the RX-8 you are driving pulls to one side it may have a sticking/seized caliper. Seized calipers can occur if vehicle has been left standing for a period of time. If a brake caliper has seized, you may notice a load thud when you pull away for the first time.
A judder through the steering wheel under braking may be an indication that the discs are warped and need replacing. This will probably first become apparent under high speed braking.
Any other loud or strange noises should be investigated closely as they can be a sign of a number of expensive issues. Additionally, if the brakes feel weak or struggle to stop the car properly there is a problem.
Aftermarket brakes are available for those who want a bit more stopping power, but the standard ones are more than adequate for road use and even some light track use. If the aftermarket brakes are from a cheap or no name brand you should not purchase the vehicle.
Additionally, ask the owner/seller if they have the original brakes. If they don’t, try to get a discount.
Wheels and Tyres
Check the wheels to see if they are curbed or damaged, and if they are aftermarket ones check with the owner to see if they still have the originals. Additionally, take a good look at the tyres and check for the following:
- Enough tread
- Uneven wear (Can be a sign of alignment or suspension issues)
- Brand (make sure it is a good one)
Interior and Electronics
The interior on these cars is generally durable but you may hear some rattling, especially on cars that have not been maintained well. RX-8s that feature a sunroof or the optional sat nav will rattle more and if there is a creak from the rear, it is probably the bolt that locates the rear screen and it needs tightening.
If the steering column sounds like it is creaking, it’s not, it is the lower left front bolt on the driver’s seat. Most RX-8s will have this problem and to fix it you can put a small piece of cardboard under the washer.
Look out for any rips, stains or tears on the seats and other parts of the interior. Replacing the material on the seats can be expensive, so make sure they are in good condition. Take a good whiff of the interior, does it smell like somebody has smoked in it? Additionally, look at the headliner above the driver’s seat, if there is a stain or it is a slightly different colour to the rest of the headliner it indicates a smoker has owned the vehicle.
It is important to check that the seats slide on the runners correctly and that they do not move under braking or during acceleration. If they do move it is incredibly dangerous and it will lead to a MOT/WOF failure.
Remember to check the steering wheel, gear shifter, pedal and carpets/mats for wear as they can indicate how far an RX-8 has travelled. Excessive amounts of wear for the distance travelled could indicate that the car’s odometer has been wound back.
During a test drive and inspection of an RX-8 make sure all the buttons, switches and toggles work correctly. Inspect the dash for any warning lights. If there are none during start up the car may have an issue, or the owner may have disconnected them to hide an issue.
Aftermarket components need to be inspected closely to make sure they work and are installed correctly. Poor workmanship here can be a sign of a careless owner.
How to Drive a Mazda RX-8?
It is extremely important that you warm a car (any car not just rotaries) up properly. Always let a vehicle come up to the correct temperature before planting your foot on the floor. For the RX-8, keep the revs under around 4,000 rpm until the temperature needle is pointing straight up (a slight shift is normal on the gauge).
When the car is up to temperature, give it some revs. Rotary engined cars handle high rpms extremely well and if you stay low in the rev range you will find that the RX-8 feels gutless. Additionally, if you don’t rev an RX-8 hard, carbon can build up which can kill the engine.
With all that said, high revs generate a lot of heat and increase fuel consumption. It is best to cruise around at around 4,000 – 5,000 rpm and then take it up to the redline occasionally.
How to Turn Off a Mazda RX-8?
This is a slightly ridiculous question, but it does get asked quite frequently. There is no special procedure, just make sure the car is warm and the ignition system is in good condition. Try to avoid short journeys in an RX-8 as this does not let the engine warm up properly.
General Car Buying Advice for the Mazda RX-8
How to Get Yourself the Best Deal On an RX-8
This information applies to both dealers and private sealers. Knowledge is power and it can save you a lot of money when purchasing a vehicle.
- Do your research. Before you start your search for an RX-8 make sure you know what model and condition you are happy with. Are you okay with a highly modified RX-8 or do you want something that is completely stock? Do you want a low mileage example or are you happy with a car that has travelled far?
- Shop around. Don’t limit yourself to just one dealer, seller or location. Check out various different dealers and sellers to find the best car and get the right price. Limiting yourself to just one area will make it more difficult to find your dream Mazda RX-8.
- Test drive multiple cars. Don’t just take one RX-8 out for a test drive and then buy it. Drive as many GT-Fours as you can get your hands on. This will give you a good idea of what makes a good and what makes a bad Mazda RX-8.
- Adjust your attitude. Don’t rush into purchasing any old RX-8. If you are desperate to buy a car you are more likely to get ripped off. Take your time looking through all the different vehicles available and then go inspect the ones you think look promising.
- Use any issues with the car to your advantage. Take a mental note of any issues you find with the vehicle. When it comes to discussing the price, use these problems to try and drive down the price. For example, if the car needs new tyres or brake pads make a point of it and try to get the seller to reduce the price.
- Don’t trust the owner. While some owners/sellers are honest about their cars, many will lie to get a quick sale. Take in what the owner has to say, but check out the vehicle thoroughly and inspect all the car’s documentation.
- Bounce between sellers/dealers. If you are looking at multiple RX-8s, let the owner/seller know. This way they will know that you have other options and they may try to undercut the price.
- Be prepared to walk away. If you are not happy with the deal, simply walk away. You may miss out on the car or the seller may get back to you with a better offer.
Mileage vs Condition
Mileage vs condition is always a big debate, but we recommend that you should always buy on condition and then on the mileage. There are plenty of RX-8s out there with low mileage but in poor condition, while some high mileage examples may be perfectly fine.
Lots of owners make the mistake of believing that they are preserving their car by not driving it. In reality, this is completely false and not driving a vehicle can actually do more damage than good. Short distance trips are not kind to an RX-8’s rotary engine as they do not have enough time to warm up and get lubricated properly.
Rubber seals and plastic parts will fail regardless of mileage and can even deteriorate quicker on cars that don’t get used often. Letting a car sit will not prevent rust or stop the electronics from failing.
Mileage will never decrease with age, so go out and drive your car!
Service History and Other Documentation
It is incredibly important to check any vehicle’s service history and any additional paperwork that goes along with it. The service history will give you a good idea of how the RX-8 you are inspecting has been maintained. In addition to this, receipts and paperwork for modifications can help you determine whether they have been done by an experienced tuner or a bad one.
If the owner can’t or won’t let you see the service history, you should probably pass on the vehicle. A complete service history will only add value to any Mazda RX-8 and will make it easier to sell the vehicle in the future.
Additionally, you can check websites such as CarFax (USA) and CarJam (NZ) for more information about the car you are thinking of purchasing. These sort of websites can be incredibly useful, but there is usually a cost associated with them.
Questions That You Should Ask the Seller/Owner
- How often do you drive the car?
- When was the last service and who was it serviced by?
- How much oil does it use?
- What oil do you use in the car?
- Has the car every flooded
- What parts have been replaced (engine, catalytic converter, etc.)?
- When were the coils, spark plugs, leads changed?
- What’s the compression like?
- What modifications have been made to the vehicle?
- Has the vehicle overheated at any point?
- Has the car been in any major or minor accidents? Is so, what repairs were made?
- Is there any money owing on the car?
- Have you got any information on the previous owners and how they treated the vehicle?
- Is there any rust?
- Has rust been removed at any point?
- Has the car been used for track use at any point?
- When were the brake pads replaced and have the calipers seized at any point in time?
- Where do you store/park the car usually?
There are loads more questions you can ask the seller, but we feel these are some of the most important.
Things That Would Make Us Walk Away from an RX-8
Sometimes, the best option is to simply walk away from a vehicle. While you may be happy with a vehicle with these problems, we are not.
- Overheating problems
- Significant Crash Damage
- Money owing on the car
- Modifications with no paperwork or carried out by a poorly reviewed tuner
- Excessive amounts of power
- Bad compression
- Bad resprays
- Significant rust problems
- Engine swaps with non-standard engines
- Significant track use
- Major engine or transmission issues
- Owner who is not forthcoming with information (could be trying to hide something)
Notes on the Owner
The owner is one of the most important things to think about when viewing any vehicle. You need to ask them plenty of questions when inspecting their Mazda RX-8 (however, don’t trust their answers completely). Remember, it is your problem if you wind up buying a dog of a car. Below we have listed some things to consider about the owner.
- How long have they owned the vehicle? If it is less than 6 months it tends to suggest that the car needs major work done to it that they can’t afford. It also could be a sign that they deal cars as well.
- Do they thrash the car when it is cold or continually launch the vehicle? If so, you are better to walk away.
- Why are they selling the vehicle? Could be a genuine reason or they may be trying to offload their problem onto an unsuspecting buyer.
- What sort of area do they live in? Is it a good area or a complete dump?
- How do they respond when you ask them simple questions?
- Do they know anything about the RX-8 and the model they are selling?
- What can they tell you about previous owners?
- Do they have lots of cars on their drive? If they do it may mean they are a dealer.
- What is their reaction when you ask them about money owing on the car? Tell them you are going to do a check and see how they respond.
- What is their reaction to you asking for details for HPi check?
- How do they react if you ask to do a compression test on the vehicle?
- How do they respond when you ask them to show you the service history and paperwork for the car?
If you get a bad feeling about the owner, you are better off moving onto another RX-8. Mazda made quite a few so you should be able to find plenty of good examples out there.
Where to Find a Mazda RX-8 for Sale
Websites such as Craigslist, Kijiji, TradeMe, Piston Heads and GumTree are great places to start your hunt for an RX-8. You will find a range of RX-8s for sale at different prices and in different conditions. You can easily compare the price, specs and condition of different Mazda RX-8s and you will be able to select the ones that look promising.
Dealers and Importers
Most dealers and importers will have an online presence, so make sure you check out their website for any RX-8s for sale. Dealers tend to be a bit more expensive than private sellers, but sometimes you can get some extras thrown in or better protection.
Websites such as Reddit, Facebook and even Instagram can be excellent places to find RX-8s for sale. Check out some of the many enthusiast groups or subreddits and let other users know you are interested in buying an RX-8. Additionally, social media groups are often great places to find spare parts or get advice from other owners.
This sort of ties in with the above, but many owners’ clubs have their own website or they may not even have a website at all. Look to see if there are any Mazda or RX-8 clubs in your area as these are often great places to find cars for sale or ask for advice.
Importing a Mazda RX-8 from Japan
If you are struggling to find a suitable RX-8 in your country, you may want to look at importing one from Japan. A large number of RX-8s were sold in Japan, so it is a great place to find them for sale.
Exporting vehicles from Japan is a big business as it keeps the country’s motor industry moving and older vehicles become more expensive to run. Below we have outlined everything you need to know about importing a Mazda RX-8 from Japan.
How to Import an RX-8 from Japan
While importing an RX-8 from Japan may seem a bit daunting, it is actually quite easy. The first thing we recommend you do is to Google search “import Mazda RX-8 or import car from Japan”. You will be greeted with loads of different websites to choose from. These websites will let you search for RX-8s based on their age, generation, condition, price and more.
Most of the websites/companies you encounter should be based in Japan, but you may find some other ones that are located in different parts of the world.
Make sure you check reviews/feedback of any website or auction house you want to use. While you are unlikely to get completely scammed, many of these websites will be economical with the truth about a vehicle. We have listed a few examples of Japanese importers/exporters below:
Goo net Exchange – Is one of the biggest vehicle exporters in Japan and they have head offices in Tokyo and Nagoya. They have a large selection of cars ready for export.
JDM Expo – Is an independent subsidiary of Nikko Auto Co., which is recognized as on the most reliable exporters of Japanese cars in the country.
Car From Japan – is another large portal for connecting overseas buyers with Japanese second hand cars. They have a number of vehicles ready for export.
Japan Partner – Is one of the fastest growing exporters of used Japanese vehicles and they have a range of RX-8s for sale.
Note: many of these sorts of websites do not provide a grade or auction check sheet. The grade, auction check sheet, and car map are vital to picking a good car. Buyer beware!
Why You Should Use a Private Importer
While the websites above are handy to give you a general idea of what to expect when importing an RX-8, we recommend that you go with a private importer. A trusted private importer will be able to find the perfect RX-8 for you and import it, saving you the hassle. While it may cost you a bit more (sometimes it is cheaper) you are more likely to get a better vehicle.
You can get a full explanation of why we recommend using a private importer here.
How Does the Japanese Car Grading System Work?
The auction houses and car exporters in Japan all get their vehicles in roughly the same way. The difference between them is how much support they are willing to provide, how honest they are, and how they grade their vehicles
They will provide what is known as an ‘auction check sheet’ – a document that contains most of what you need to know about the vehicle. As you can’t see the vehicle personally, you will have to rely on the check sheet and other information on the listing to make a decision. If the seller/website is not willing to provide you with an auction check sheet or additional information on the car, don’t proceed any further.
Before you make a purchase you need to learn how to read an auction check sheet. The sheet contains information on the make, model, condition, specifications and any other notes. There will be a grade on the sheet that denotes the overall grade of the vehicle.
While the grade on a check sheet is important, you should not rely on it to make a final decision. Different companies have different methods for grading their vehicles, so a grade 4 for one company may be a grade 3.5 for another.
Some websites may use a different grading system and if you can’t view the auction check sheet, you should contact the seller/exporter.
Use the grade to whittle down the number of RX-8s you are looking at and then use the check sheet and additionally information to make a decision. We also recommend you pay a third party to check out the car for you.
The Auction Check Sheet
Below you can see an example of an auction check sheet. The grade is located in the top right corner of the check sheet. You will notice that there is both a letter and a number grade. The number indicates the overall condition of the vehicle, while the letter shows you the interior grade. At the bottom right of the check sheet is the ‘car map’. The car map tells you information about the exterior of the Evo and where any problems are located.
Additionally, the sheet contains information about the specs of the vehicle and any modifications (major or minor). The inspector may also write some additional notes about the car.
What Does the Number Grade Mean?
- Grade 7 to 9 or S– New car with delivery miles.
- Grade 6– Same as above but with a few more miles.
- Grade 5– Vehicle is in excellent condition with low miles.
- Grade 4.5– Overall condition is great, but may have up to 100,000 miles on the clock.
- Grade 4– Overall condition is good, but can have low or high miles.
- Grade 3.5– Similar to grade 4, but some work may be needed and they usually have more miles.
- Grade 3– Can be the same condition as grade 3.5, but with more miles. Alternatively, the car may have lower miles but require more work.
- Grade 2– Very poor condition car and may have significant mechanical or exterior issues. Not necessarily a right off, but you would have to be a brave buyer to purchase one of these.
- Grade 1– Is modified in some way (can be extensive or something simple).
- Grade 0, A, R, RA– Some repair history that can be major or minor.
The Letter Grade
As we wrote earlier, the number grade is usually accompanied by a letter that indicates the interior grade. An ‘A’ indicates that the interior is in exceptional or good condition. A ‘B’ indicates that the car is in average condition, while a ‘C’ displays that it is in poor condition. Grades below C show that the car’s interior is in very poor condition.
The Car Map
The check sheet will also contain what is called a “car map”, which tells you all the information you need to know about the exterior condition of the car. It will show the location of any problems or damage to the vehicle. Any problems are indicated by a letter and a number. The letter tells you what the issue is and the number indicates the severity. You can read more about the car map in our “How to Import a Car from Japan” guide.
Our Guidelines for Importing a Mazda RX-8 from Japan
- Always demand to see and have the auction check sheet before making a purchase
- If you can’t read Japanese or the company won’t provide a translated check sheet, get help from somebody who speaks/reads Japanese.
- Try to go through a private importer
- Check that the chassis number on the check sheet matches the one on the frame
- Cross reference the check sheet with other websites
- Don’t rely on the grade (always check the auction sheet thoroughly)
- Investigate each website/service thoroughly (reviews, feedback, etc.)
- Be careful of heavily modified vehicles
- Get someone to inspect the car for you if possible. Ask for photos and get a good run down of the condition.
- Avoid cars with unknown mileages
- Stay away from bargains that seem to be too good to be true
- Stay away from grade 0, A, RA, R vehicles that have been involved in accidents
Know Your Country’s Importation Laws
Always make sure you check your country’s importation laws as you may find you can’t bring the vehicle you want in. For example, some countries have certain restrictions on importing cars under a certain age.
Summary of this Mazda RX-8 Buyer’s Guide
This guide should cover most of what you need to know about purchasing a Mazda RX-8. While this guide may make it sound like a bit of a nightmare, it really isn’t. If the RX-8 you are looking at has been well maintained, driven properly and has a respectable owner you are probably okay.
We will continue to update this article with more information and make sure you check out our classifieds section of the website.
https://www.rx8club.com/ – Excellent forum with knowledgeable users. Much of the information for this guide came from there.
http://www.rotaryheads.com/PDF/RX8/ – Service and technical manuals for the RX-8