Randall

I almost always get a pinking sound whenever I'm at about 1750rpm. The sound is somewhat continous and it goes away when either I go lower in rpm or when higher. This sound doesn't occur at any other rpm range.

It's a 1995 w202-C220

Any clue as to what causes this sound?

praveen

i have the same thing on my e220cdi w211 and the dealer told me it was extra detonation in order to maximize fuel burn efficiency and minimize emissions. He said it would cause no harm to the car. dunno if this helps,,,

Untertürkheim

Sounds like low quality fuel or your car needs service.