I have a 1988 Audi 5000 CS TQ with 173000 miles. Last month the car started to have 2 misses at cold start (cant remember for hot starts) that you could actually HEAR go away after the first 30 seconds of running. Some days it would only be one cylinder misfiring that would go away. One day the single misfire became permanent and I took it to a shop that took it on the freeway and beat on it. The next day I picked it up and the misfire was gone. A week later I was boosting and noticed the boost was lower (13 psi compared to 16 psi with cpu chipped) than normal and then parked at home and let sit over night. The next morning the misfire was there and hasn't gone away since. The idle is shaky and the engine hesitates/lower power. I suspect a stuck valve of some sort. I pulled the valve cover and found burned up oil on the underside of the cover but not on the engine. Oil smelled of gas, as well. The technician at Auto-RX told me my PCV system might be malfunctioning, but I cant locate the actual PCV system on my car.

Any ideas on the misfire issue? Does anyone know where the actual positive crankcase VALVE is on this 5 cylinder turbo engine?

I looked on ETKA and it says the 3-way rubber boot on the valve cover is a valve container or something but when I pinch this hose all around it is soft like a hose should be and not hard as if there where a valve somewhere inside it.

 

Found out for myself...there is no valve anywhere in the system. Vacuum is provided upstream of the intake.