Name that 2002 GTI engine sound

I have a 2002 VW GTI 1.8T (80k miles) that is making a louder than normal idle sound coming from the timing belt side of the engine. I’ve put a sound file up:


The frequency of the sound increases when the engine revs up.

I tried to locate the source of the sound using the ears but it is hard to pin down.

The noise has been occurring for a while now and does not appear to affect driving or idling.

Any ideas welcome,



I couldn’t tell but that’s not unusual to me because I can hardly ever make heads or tails out of an MP3 file like this.

If the timing belt has never been changed then it’s way past due and the car really should not be driven or very little. This also means any idler or tensioner bearings and water pump. When this job is done things like accessories and accessory belt tensioners can be inspected.


Yes, the recording sounded like a good idea at first!

The timing belt still needs to be replaced as the VW manual recommends this to occur at 105k which may be tad late. Since my thermostat is likely to be stuck in the open position as well (causing slow engine warm-up and subsequent “engine cooling malfunction” error codes) I think I will bring the car in for both that and the belt work.

There is another factor in regards to timing belts and it’s not mileage. It’s age and generally speaking, 6 years is about the limit on timing belts.
Timing belts have been known to break long before 6 years or a 100k miles as some good friends of mine found out on their 59k miles/4 year old Honda Civic.

It does sound like a thermostat is acting up but that’s not unusual either. It’s aged and in my opinion a T-stat is something that should be changed about every 3 or 4 years. I look at them as a cheap maintenance item and better stuck open than closed. Many an engine has been barbecued by a 5 dollar thermostat.

Good point, and given the amount of damage the timing belt can do to the engine it’s better to bite the bullet now.
Thanks again for the advice.