Can anyone help a new B6 owner

[Geoff Mulligan]

Hi all, I'm new to the forum and after searching the forum for answers I thought best to ask if anyone can help. My B6 2.5 Avant has developed a lumpy idle, its fine when being driven but pulling up to lights it shakes the steering wheel and gearknob quite badly. The top end had been rebuilt by the previous owner but Ive no idea if he had the problem with idle, Ive just bought the car and it does spoil the drive. Ive looked online at possible causes but as I'm new to the car and not had it serviced yet, should I bother starting with injector cleaner and go from there or is it likely the timing ? Thanks for looking and hope you can help

 

[a6allroader]

Hi and congrats on the new motor I recently bought one and it was rough on idle but only intermittently...it was overdue a timing belt change so the first thing it had done was the cambelt, water pump and the pulleys. The guy who did the job told me that one of the pully kinda fell apart in his hand when he removed it which makes me think that may have been the issue with mine as it wasn't there all the time. May be an idea to try get the codes read to see if anything shows up there?

Good luck

 

[QuattroCalum]

Check the accessory belt tensioner, that can cause vibration if it's past it's best, start the engine and have a look, if it doesn't run smoothly you know the answer. Might not be this but it's the cheapest option and easily checked.

 

[Geoff Mulligan]

Many thanks for replying gents,the cambelt and pulleys were done last year supposedly so I need to book the car in to get it checked out. I will have a look to see what the belt is running like and do a bit of investigating. It does seem that others experiences with poor idle seems to be either belts/pulleys or the fuel system

 

[abyrne153]

DMF maybe?

 

[adamss24]

Yep, the center bearing on dual mass flywheel is worn, replace with new clutch and flywheel !

 

[Pops848]

Depends on the vibration, and if idle is affected.

My experience of a DMF failure was that you'd here a slight rattle but the car would vibrate. Not so much that it would shatter your need but the engine would stay pretty solid

Compare that to a misfire and the vibration was AWFUL

So I'd say if all belts etc have been done, and the engine speed at idle doesn't fluctuate too much then yes, DMF could be the culprit, circa £500-£850 job (depending on parts and labour obviously)