Just got through replacing both crankshaft position sensors on my 1999 S600 - a job for VERY small hands! Well, after putting everything back together, I found one plastic cover still sitting on the bench. I have looked all over this engine and the gone through the W140 manual truing to find it - no success. It's a black cover (looks like a duct cover) about 4 inches long, 2 inches wide with a 2 inch M8 bolt for attachment. Part number is A120-150-11-15.

Anybody know where this cover fits?

 

can you describe steps for replacement procedures because right now I am after this problem and still wondering how to act underneath undone exhaust pipes or from above as you said with tiny hands
thanks

 

HOPEFULLY THIS HELPS