Hi all, recently I was replacing my throttle lever on the intake manifold and saw oil coming from engine to the intake and burning down the valves into the cylinders. Any suggestions why this is happening? Here are some pics:

 

Looks like a PCV issue, engine vacuum pulls oil mist into the intake manifold through the PCV, could be faulty.

 

Normal from the captive breather system. Rear of valve tulip is spotless. You are using a fuel with a decent additive system. Unfortunately it can only clean downstream of the injectors where the fuel can get.

 

Im trying to check if my PCV needs cleaning. Where is the PCV located? Is it the 1 pic that i have uploaded ? looks similar to this ?

 

Yes, that is the PCV. Your car may benefit from a catch can whereas the oil mist goes through a collection can before the manifold.

 

Hey all!
I removed my intake manifold today to replace a broken swirl flap actuator arm and was also shocked by the amount of oil in the intake manifold and the amount of grunge in the intake ports. I've attached a photo of the rear passenger side intake port. Our GLK350 had nearly 200,000 miles on it. Is this just normal for an engine with this many miles?

I also replaced the PVC cover that is in the above photo, so hopefully the amount of oil coming into the manifold in the future will be greatly reduced.

Once I get everything back together, what's the best way to clean up those intake ports? Or should I squirt some carb cleaner in there now and just let it evaporate before I put the intake manifold back in place?

Also, the actual plastic swirl flap things inside of the intake manifold are drenched in oil. Can/should I spray those down with carb cleaner?

Thanks in advance!

Mike

Grunge!