2.0 tdi revs the whole way around to limiter when i go to change gear??

[AudiABT]

Hi, I have just bought my second 2.0 tdi A4... the car is revving uncontrollably. It has done it twice now, when changing gears between 2nd and 4th, when i press the cluth pedal and put it in nuetral, the car revs around to the limit and the only way to stop it is to switch off the engine...when you start it again, there is a huge puff of white smoke from tyhe exhausts and then all is ok. Any idea what the problem is? or has anyone had a similar problem? thanks.

[Crasher]

There are a couple of possible causes. Faulty clutch pedal switch (unlikely though), a fault with the accelerator pedal electronics such as water in the plugs (but this should stop the engine revving at all), a faulty engine ECU (never seen this happen but I have heard of it) or oil being sucked into the engine during hard acceleration. This can be due to a failed tandem pump or turbo problem. Check your oil level as if it is going up, it may be the tandem pump and this has been known to cause catastrophic engine failure.

[AudiABT]

Thanks, the low oil warning came on about two days after this has happened and I topped it up immediatly and then it happened again. Could the extremely low temperatures and snow have had an effect? thanks again.

[brum_s4]

this is confusing buddy all i can say that get a VAG com laptop put on it or take it down a mechanic it could be a electrical problem or could be something mechanical when was it last serviced etc etc

[Crasher]

Your engine is sucking oil and if the level is going down I would suspect the turbo but it should grey smoke all the time if that is the case. The over revving is the engine running on the sump oil.

[Columbo]

If it is sucking in oil you need to be carefull as this will let it rev above the rev limiter and destroy the engine.

Have you got the DPF fitted to you car. These can mask any smoke caused by a poorly engine.