[s-cars] Non S-Car: A4 Stumble

[Tihol Tiholov]

First time poster here, hello everyone,
I'm chasing down the exact same problem on VW NBeetle 2.0, only the
codes are for random misfires and also cyl. 1 and 3.  The other
difference is that my idle gets irregular after 2-3 minutes and
someone suggested OXS for that.  I'll go on looking on Saturday and
share progress if any.

>Could it be bad ignition wires?  I had a similar situation on my 200 
five years ago.

Replced those, no change, due anyway @ 221K km

>My wife's A4 (96 12v V6) is having a stumble  under load problem ...
>Car seems fine, idles fine, etc. Sometimes under  load (accelerating
from 2k rpm in 3rd gear) the car begins to stumble  badly. It feels
like a pre-detonation and drop back in timing; however, the  gas is
what she has always used without problem. I hooked up VAG-COM  and
sometimes an error code is logged:
16689 - cylinder 5 misfire  detected
p0305 - 69-00 - cylinder 2
(I'm not sure what that  cylinder 2 part of the above message means).

P0305 is misfiring cyl. 5, DK what 69-00 is but VAG-COM should have
mentioned it.

>This code does not always  appear after a stumble incident (if I
clear the code, go drive and get it  stumble); however, it always
comes eventually. I have moved the plugs  around, tested the coils,
plug wires, PSO, etc. and nothing has had an  impact. This car has
three coils and one PSO so, if the coil were the  issue, I should
register misfires on cylinder 3 also (since 5 and 3 are on  the same
coil).
>It doesn't ever turn on the CEL, but, sometimes does  enter the above
error code. The misfire detection (as I understand it) will  flip the
code if there are any slight deviations so it is only an  indicator, I
suppose.
>I have thought about poor fuel delivery, FPR,  etc.; however, any of
those issues should register misfires on other  cylinders, not just 5.
-- 
Tihol,
No S4 yet but looking