I'm a newly. Driving a 2009 W164 Bluetec. For those who are having signs of oil inside the turbo intake, here's how I solved my problem. The air filters! Check the air filters. If they are dirty, the intake air has to come from somewhere, right? In my case the intake air was coming from the crankcase, thus "sucking" oil fumes through the crankcase breather valve.

Not sure what kind of pressure check valves are part of the breather system, but mine are fatigued by the continuous demand for intake air and thus the turbo is "pulling" crankcase oil vapor into the intake port.

Am in the process of replacing the breather valve, bloody knuckles and all, but it should eliminate the sign of oil.

Any suggestions or opinions are welcomed!

 

moved to W164 forum...