Engine sounds a bit like a diesel when warmed up, 2008 GTI,55000 miles

[westworld]

Hi All

Recently i have started to hear a slight thumping noise when im sitting inside the car when its in idle example waiting at traffic lights, sounds a bit like a diesel in idle, but when i touch the accelerator very slightly the noise stops and its as sweet as a nut.

I have read on hear about the cam chain& tensioner it could be, but the noise vanishes as soon as the accelerator is touched.

Any ideas.
The car does seem to tick over at  very low revs so wondering if it idled a fraction higher in revs would the knocking stop?

Cheers Guys hope it kind of makes sense.

[Gmaster]

Theirs a long thread on this issue try a search.
But yes most likely cam chain just had mine done it sounded like a diesel inside the cabin really quiet loud!
Nice and quiet now though.

[westworld]

Thanks so when the cam chain has been done its all quiet in the cabin, sorry not been in any other GTIs so i cant compare. Still got warranty on the car as only owned it for two weeks.

[Gmaster]

This is my first mk5 gti so didn't realise myself but I thought this don't sound right so starting looking into it a very common problem by all accounts.
I can't believe how much better mine is now is like a different car.
I had just the chain and tensioner done sometimes you need to get a new adjuster which is a £300 part.

[GTi-Andy]

I'm too a member of the non-diesel sounding club!

Had mine done about 3 months ago, so much quieter now and no diesel sound in the cabin which was embarrassing to be honest.

I'd say if you can hear a diesel sound when in the cabin then get it done

[westworld]

Just been for a drive in it, the noise is only there when it settles down at 700 rpm that's what this car idles at, touch accelerator say 800rpm the noise is gone  does that sound right??

Was wondering is it vibration from the exhaust when its ticking over.

Or is this still a symptom of cam chain issue? Can only really hear it in the cabin, open the bonnet it sounds ok just hear the Tappets sound round by the alternator area.

[GTi-Andy]

Sounds like typical diesel syndrome mate. Mine did the same. Never really heard the diesel sound until in the cabin on tick over and then it would go when pressed the accelerator.

[Matthewsimone]

Mine is a 57 plate on 73,000 miles and sounds smooth as a baby's bum bum so really does seem like pot luck with the diesel noise
My previous 2006 Gti sounded awful after only 40,000 miles and was only 3 years old at the time too 

[westworld]

Hi
All sorted now, been to the garage they had it on the ramp ,It was one of the Heater type hoses had come loose from its clip thats all it was .

Nice and quiet now ..

[pudding]

Has anyone considered that this whole issue could be inlet valve clogged up with carbon causing a slower idling quality??....

I had my inlet valves cleaned out, idle in gear with air con off before the valve cleaning was always 720rpm, out of gear 760 -800 rpm, now it's much smoother at 760 in gear and 800 with aircon on, so smooth in fact you cannot feel the engine load up when you take it out on N into D.
I used to feel the car shake slightly when engaging drive, now you cannot feel switching gears whilst sat stationary.

It's worth check guys if your car idles really slowly , check on VCDS, your live misfire count.

The ECU should open the throttle body until the target idle rpm is met.  If that isn't happening, I'd say something else is up!  A throttle adaptation can sometimes help, and I say sometimes, because the ECU usually does everything itself automatically.