Audi TT Mk1 – When To Replace the Timing Belt?

Replacing the timing belt at the correct interval on a 1999 to 2006 Mk1 Audi TT is one of the most important things you can do.

This is because a belt failure can lead to some pretty nasty consequences and leave your wallet feeling significantly lighter. In fact, a broken timing belt (aka cambelt) on a Mk1 Audit TT could potentially cost you more than the car is worth to fix.

In this article we are going to look at the correct Mk1 Audi TT timing belt interval, as well as answer common questions about this critical service item.

Does the Mk1 Audi TT have a Timing Belt or Chain?

Well, this depends on the model you are looking at.

The 3.2-litre V6 engine uses a chain, while the 1.8-litre turbocharged unit uses a timing belt, so if you have the former you don’t have to worry about changing the chain at a certain service interval (however, there are some things to keep in mind with chain driven motors and we will get to them later in this article).

When Does the Timing Belt Need to Be Replaced on a Mk1 Audi TT 1.8?

Credit: Audi

Referring to some older Audi service manuals, the recommended service interval for the timing belt on 1.8T engines is set at every 160,000 km (100,000 miles). However, that advice was changed and an earlier replacement at around 100,000 km (62,000 miles) is now recommended for all 1.8-litre Mk1 TTs. The earlier replacement was suggested due to known weak points in the engine, particularly the hydraulic tensioner.

If your Audi TT doesn’t see much action, it is generally recommended that you replace the belt every 4 to 5 years.

To recap, the Audi TT Mk1 timing belt interval is as follows:

  • 100,000km/62,000 miles for the 1.8T engine OR 4-5 years (whichever comes sooner)

What Happens if the Timing Belt Breaks on a Mk1 Audi TT

Unfortunately, the 1.8-litre turbocharged engine under the hood of the Mk1 Audi TT is an interference engine. If the belt and/or tensioner fails, the valves may collide with the pistons, leading to severe engine damage and an extremely expensive repair bill.

You can check the condition of the belt and tensioner by listening out for any unusual sounds coming from the timing belt area. If you hear noises such as rubbing, squeaking, tapping, or ticking, it could indicate the belt and tensioner are past their due date. Physical inspection of these components is recommended for a more accurate assessment.

What Else Should be Replaced with the Timing Belt?

When replacing the timing belt, consider also changing the following:

  • Tensioners and idler bearings: These components are also susceptible to failure, and an issue with them could lead to belt misalignment or failure.
  • Water pump: The pump should be replaced around the same time as the timing belt to reduce the risk of future issues.
  • Thermostat
  • Timing cover gasket and cam chain tensioner gaskets: These components often develop leaks, especially after 120,000 km (75,000 miles), so preventive replacement is wise.

What About the Timing Chain on the 3.2-litre Audi TT?

Credit: Audi

As we mentioned earlier, the 3.2-litre power unit uses a timing chain instead of a belt and you don’t have to worry about changing it at a specified interval. However, while the timing chain should technically last the lifetime of the engine, in reality it can be quite different.

Unfortunately, some owners of 3.2 Mk1 TTs have had the timing chain/tensioner fail on their cars. It seems like problems often start to occur around the 160,000 km (100,000 mile) mark and above, but they could occur earlier as well.

If the chain or tensioner is starting to fail, you may notice a strange rattling from the right side of the engine.A loose timing chain can also cause misfires as well, so check for that if you suspect their may be an issue with your TT Mk1.

The most likely cause of timing issues on an Audi TT 3.2 is not actually the timing chain itself, but is in-fact the plastic tensioner. This tensioner eventually wears and while it is not too expensive to replace by itself, it is generally recommended that you get the whole timing set (chain, tensioner, guides and all) replaced at the same time.

To Sum Up – Mk1 Audi TT Timing Belt Interval

On the Mk1 Audi TT 1.8T, it is recommended that the timing belt be replaced approximately every 100,000 km (62,000 miles) or before. If this mileage is not reached, the belt should be replaced every 4 to 5 years. When replacing the timing belt, the tensioners, idler bearings, water pump, thermostat, timing cover gasket, and the cam chain tensioner gasket should be replaced as well.

As the 1.8T is an interference engine, if the timing belt does fail it will cause severe damage to the engine, resulting in an expensive repair bill.

The 3.2 TT from this generation doesn’t uses a timing belt instead of a chain. While it should last the lifetime of the engine and there isn’t a recommended service interval, the chain and/or tensioner can fail. If a failure does occur it can lead to strange rattling noises from the right side of the engine and possibly misfires as well. A complete failure will lead to more serious problems, but this is unlikely. The most critical thing to keep your timing chain in good condition is to regularly service your car. 


  • Ben

    From his early days playing the original Gran Turismo and with his Hot Wheels car set, Ben has had a long interest in all things automotive. His first foray into the world of automotive journalism was way back in 2009 and since then he has only grown more interested in the industry. Ben also runs and heads up the video production side of Garage Dreams, focusing on small informative documentaries about some of the world's most legendary cars.

Leave a Comment