I am guessing this is the 1995 E320 Special Edition 202,000 miles.

Diagnosis should start with:
* Replace the leaking valve cover gasket.
* Replace the spark plugs, MB# 0031596703.
* A cylinder leak down test.
* A compression test.

Checking for worn out valve guides and seals, and/or bad piston rings.





Have a great day.

__________________
ASE Master Mechanic

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