like you have a lot of carbon build up. i would give it a dose of injection cleaner and run it hard in third gear for ten miles or so to get the carbon good and hot and hope to blow it out.

ricks comments about oil consumption are good. the one cyl sounds as if it may have those.

if your car is new to you it may not have been getting regular oil changes or maybe not good oil. perhaps a good synthetic might clean out your rings if they are stuck. broken rings in a benz seem unlikely.

non of this will help if valve guides and seals are shot.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.