Revs fall slowly

[xXShaggyXx]

Hi,

I've recently bought a Mk4 GTi -it's the 2.0 litre, 115 bhp- and I've noticed that the revs fall down VERY slowly back to idle once the engine has warmed up a bit. This happens either on neutral or by having the clutch pressed while on the move.
Note that the accelerator pedal doesn't get stuck or anything.
I might add it feels as if it doesn't really have 115 bhp. I know its not much, but it's not the heaviest car either!

Any ideas of what it might be?

Cheers
Juan

[JWebb]

Hi Juan,

First thing to do is get the car scanned with Vagcom to see if there are any codes thrown up by the car, that should be your first port of call. Also make sure the cam belt and water pump have been changed recently as these are common to fail and is worth while doing.

In terms of your revs dropping slowly try cleaning the throttle body you should notice a sharper throttle response once this is done, it could also just be caused by the OE flywheel being heavy, people often change them for lighter aftermarket ones but this might be out of the question dependent on budget etc.

 I'll have a look later to see how quickly my revs fall down and let you know, does it happen from anywhere in the revs or is it worse the higher you go?

I also have a 2.0 GTI and they aren't quick cars so don't expect too much from it! however as I said try and get it scanned for codes that'll let you know if you've got a problem.

No doubt the rest of the guys will be able to shed some light/ideas as well!

Jack.

[xXShaggyXx]

Cheers Jack, I'll have a look later on at what you suggested and I'll experiment a bit more both in high revs and low (it does it on both, but I only tried once on high revs.)

I did have a look at the cambelt before as it had no service history and it looks fine (no "dents", strings, etc.). In any case, how often does it have to be changed?