Good Day!
My 2003 Mercedes C180 Kompressor, manual, with 140k Kilometers, has a P0020 code. It also has codes P0136 and P0141 codes, but I just pulled the plug on my downstream O2 sensor and it was full of oil, so I will clean it and the surrounding, clear that code, and see if it comes back.
My real fear is the P0020 code. The car is drivable and seems to be running normally. Maybe a bit sluggish, but nothing drastic to the point of not driving it. I have swapped Oil Control Valve positions, replaced the intake camshaft position sensor, cleaned all the plugs, and changed the engine oil/filter, but it still keeps coming back after a few drive cycles. Has anyone run into this issue with their dreaded Mercedes? Just looking for guidance before I start shooting wires/looking into timing. I appreciate the help and let me know if you have any questions.
Tony
Well, if you're downstream sensor was full of oil that thing's thrown oil and for my experience that's always some type of internal engine oil failure that oil actually gets into the exhaust system. I would start by doing a wet and dry compression test of the engine to see if any of the cylinders are just flat worn out. Now as for that code , that has to do with the variable valve timing which shouldn't have anything to do with oil getting into the exhaust. That just sets the timing of the cans. So start by analyzing the engine first. If it's worn out you just stop there and get rid of the car
