1994 740 IL PCV replacement

:frown: I have started to get a lumpy idle in my 94 740IL and of course the check engine light is on. It has 131k on the odometer. I was told by a mechanic that the pcv valve located in the rear of the intake plenumn, by the bulkhead, is the problem as its common with these cars. He added that I will see an increase in oil consumption and the rough idle is the result of the plugs starting to foul. I was also told that PCV replacement is a 5 hour job and awkward. I have the factory service manual but I can't find how to do the replacement. Is this diagnosis correct and any hints or tips you can provide will be helpfull. Ta!

That very well could be the problem what are the codes for the ckeck engine light. BMW refers to the piece you are looking to replce as a vacum check plate your manual will probable show that. the worst part of doing the job is trying to get the bolts out that hold it on they are torx heads and there is not much room to get in there to work you can cheat and do it in about 1.5 hrs. or take the manifold off which is the recomended procedure and a much longer job

I had the same problem when I bought my '94 740 il 2 yrs ago. It had 119k miles at the time. Unfortunately I cant tell you how to physically fix the problem but I had the same symptoms coupled with an occasional strong gas odor.
I used a BMW mechanic (not a dealer shop) that was reasonable and it cost me about $500 parts and labor. Good luck !