[Biturbos4] Check engine light

[Mark R]

No, that's no indication of an impending timing belt problem, but you're at
the mileage for one as preventative maintenance.

Accelerating quickly when cold is not advised until the engine is fully
warmed up for any car, especially with the thermal stresses of the turbos.

Misfires when cold can be a variety of things, and would need further
diagnosis.  Could be a sticking valve, air leak, failing MAF, knock
sensor, etc.  Are there any other transient codes which would help narrow
down the focus?  Over time, is the misfire code for the same cylinder?  Does
it matter if it's wet or dry out?

There's no such thing as a "piston misfire."  By definition the piston can't
misfire!  The piston is mechanical, not electrical.  However, the code does
say (somewhat cryptically) "cylinder misfire."  Perhaps you recalled
incorrectly?  For what it's worth, these codes are fairly common as
transient codes... but if the check engine light goes on, there is a
definite problem.

Good luck,
Mark Rosenkrantz
Binghamton, NY (and also enjoying the snow/cold)

On Dec 6, 2007 10:59 AM, Aurangzeb M. Agha <ama-list at mltp.com> wrote:

> I've noticed over the last few months that when I start driving the car
> from a cold start and accelerate quickly, my check engine light turns on.
> I've checked with a mechanic who ran the VAG and said this was a piston
> mis-fire.  After four or five restarts, the light seems to go away.
>
> Now that it's gotten colder hear in the North East, I seem to see this
> problem more and more.
>
> The car is a '01 S4, and has 89K miles on it.  Could this be a sign of the
> timing belt starting to go?
>
> Thanks in advance.
>
>
> Aurangzeb
>
> --
> '01 Silver S4
> _______________________________________________
> Biturbos4 mailing list
> Biturbos4 at www.audifans.com
> http://www.audifans.com/mailman/listinfo/biturbos4
>