2.0 TDi very slow acceleration after standing for 10 days

[sprintevo]

Just got back from holiday, picked up my car and find it wont accelerate - initially it was sluggish, now it is very slow, no boost at all until 3000 rpm. when I parked it up all was fine - any possible explanation?

[simonrk57]

Maybe the VNT vanes are stuck having been left to stand? That could cause an underboost in turbo therefore putting you into Limp Mode.. Usually resets if you turn off, leave it for 30 secs, turn back on. Of course, if something is still causing an under/overboost it will continue to happen.

If you are getting boost, it is probably sticky vanes or actuator... Try working the turbo by making it boost a few times and you will probably find that it will go... Failing that, get it scanned...


Your EGR might be all coked up too...

[Crasher]

If there are no fault codes when it is scanned, fit a new genuine Audi dealer supplied exchange Air Mass Meter.

[sprintevo]

I suspect the VNT vanes too - it was a new turbo last year at 185k miles and it was never as peppy as previous and slowly it has lost some of its low down boost. if not then maybe a boost loss through the pipe-work - I know from experience that rodents like to chew Audis. car had a new MAf last month, not genuine, but GSF supplied. if the vanes come up asa code I will get this bit cleaned and also take out the cat as this was full of oil and may be blocked. Car runs normal and will boost at high revs 3,500 plus but just lost all low down tourque

[simonrk57]

Not sure the vanes will show a code..... Might just show underboost.. Have you tried coming on and off the boost to see if it frees?

[Buzzoff]

I'v had issues with MAF's from euro, I had one fail within 2 weeks of purchase and one kick the bucket just before a year was up, don't bother with them always go to the main dealer for it.