BWA TFSI Erratic Idling

Turbo Lee

Registered User

This is my first post so I hope its in the right section.

I recently aquired a 2006 A3 S-line 2.0 TFSI. I've been enjoying it up til now, as it has developed a problem when idling.

Sometimes it idles ok, but when its doesnt - it will either sit around normal idling revs but 'miss'. Or it will slowly climb the revs anywhere up til 2k, drop back down again and repeat.

It drives fine under load and seems to boost ok. Problem is only evident when idling. I havent seen a noticeable difference in MPG.

I'm concerned however that it may not be fuelling perfectly due to this problem and don't want to do any harm to the engine.

The EML is not lighting up.

Can anyone tell me what the problem is, going by what I've stated? Its a 'BWA' engine code.

Thanks, Lee


Absolute Cooling Services
You have to check plenty of things like spark plugs, spark plug wire/high tension wire, coil and grounding. Mine is doing like what you said the only fix is the grounding, they just cleaned it up and making sure that grounding is properly mounted. These are just simple things and could be the fix.

Turbo Lee

Registered User
Thanks very much for the reply. I couldn't see anything obvious in relation to what you suggested.

I've had a VAG COM scan done today, full details of which I'll have as soon as the guy e-mails them to me.

But it seemed to be pointing towards 'Leak in air intake system'. I did notice that one of the rubber mounts are missing from the plastic engine cover, at the back below the air filter. Surely this wouldn't cause a running problem as its before the MAF?

Any help greatly appreciated.