My '88 190E 2.3 is dead. Mrs was driving it home New Year's eve and it lost power on the highway. She pulled over and could not start it again. We towed it to my father-in -law's shop and actually got it running on 3 cylinders. Investigation showed ZERO compression in #4 cylinder. OK so i guess we pull the head. Having done that look at what we found! #4 piston was burned right through to the top ring. It looks like a great deal of pre igntion was happening for a long time to do this kind of damage. Strange thing is I did notice a knocking in the engine over the last 6 - 8 months but thought it was valve noise. Guess not! I do wonder though what could have caused this in just ONE cylinder. (all others look fine and so does the head (relatively speaking).

Before I rebuild this engine with new pistons i want to be sure this is not going to happen again. Any ideas?

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