NAC but VAG content: DTC code retreived

Richard J Lebens rick-l at
Wed Dec 18 20:59:25 EST 2002

The sensor that counts teeth on the flywheel sees the crankshaft
accelerate and deaccel during each power stroke.  When it runs rough
does the MIL blink at a 1 Hz rate?

How fast does the coolant leak out?  Is this the only place it's going.
 I have a GM product that sets P0305 every so often.  I can smell
traces of coolant in the engine compartment but can't find any leaks,
I'm hoping thats where the small amount of coolant I'm losing is going.
 The light goes out after 3 drive cycles but it is happening more often
now and runs bad for several minutes now.

I had a Ford that set this code and it was a head gasket with similar
symptoms to what I'm seeing now.  Head gaskets must not like me.

Does anyone know if I could further isolate the cause of the P0305 code
by any interpretation of the freeze frame data showing Long Term Fuel
Trim compared with "good" Fuel trim?  One of the possible culprits is a
bad injector that would almost have to effect fuel trim.  Is short term
adaptation stored with the freeze frame data wold that show anything?
Is it worth $150 to get someone to diagnose this using his Tech II scan
tool and hopefully interpret it?

> 16688 P0304 Cyl.4 Misfire Detected
> I also noticed a low G12 coolant level in the reservoir.
> Engine is smooth, but start-up is followed by a rough idle and black
> smoke.
> When warm everything is fine. No symptoms.
> What is the most likely culprit?
> Blown (very lightly) head gasket?
> And for the sake of knowledge, how can a system like this detect a
> misfire in a specific cylinder? What sensor can do this?

Do you Yahoo!?
Yahoo! Mail Plus - Powerful. Affordable. Sign up now.

More information about the quattro mailing list