View Full Version : Question Audi A4 afn tdi poor acceleration

19-10-2015, 08:31 PM
Evening folks,

Sorry to post what seems to be an age old question, but I can't find anything that really relates to the issue I've got with my car.

Car was bought needing an engine due to the previous owner driving it with water in the oil (screwed the crank). I've put a known good replacement from a Passat in but it has very poor acceleration now that it's in the A4. I have replaced all of the bolt on sensors for known good units, the vnt actuator is free and working, turbo is good, have run it without exhaust in case of blockage and it starts and sounds fine. The only code I'm getting is injection commencement (pump timing being done this week), but this brings me to a complete ball ache..

It has a valeo solid flywheel conversion and the timing marks do not line up to the bell housing flat. I have determined tdc using a rod through a glow plug hole and this sets the '0' on the flywheel in the middle of the bell housing window. It will not start if i try it a tooth either side of this, so I'm guessing it's correct.

Anyone got any suggestions before my brain explodes?

Thanks in advance,


21-10-2015, 08:41 PM
Bit of an update. Tried retarding the crank timing by 1 tooth and power has returned and runs smooth. New problem is that it takes ages to start when cold and smokes (fuel) badly at half throttle.

Struggling to work this out :(