Joined: Tue Sep 12, 2006 4:00 pm
Location: Rochester, NY
I am looking for ideas without throwing money at this thing. When warmed up, the car will misfire at idle in neutral (it's an auto). No issues when the car idles cold. When it is shifted into gear, the misfire will stop. Driving down the road, the car shows no signs of misfire and runs fantastic.
Recent new OEM coilpack installed
Intake smoked for leaks and none were found
210 to 230 psi compression on all cylinders
O2 correction is around 0 to -5% but bounces around quite a bit.
Misfire occurs on all cylinders
With O2 sensors unplugged, misfire only occurred on one bank and slowly disappeared when warmed up.
Put a bottle of Techron in with 1/4 tank of gas and seafoamed the intake through vacuum line. After driving about 15 miles the idle improved but still misfired. Not sure if snake oil helped or just a good drive.
My thought is O2 sensors are skewed but it seemed like an odd failure. I'd prefer not to throw money at it without some solid evidence also. Any ideas are appreciated.
1991 GTI VR6 24V
2013 Touareg TDI