Have a similar problem with my 95 C-280, along with various electrical "gremlins." So far, various dealerships and techs have replaced plugs, wires, engine wiring harness and located and repaired 2 vacuum leaks.....still runs rough and misfires! None of these folks have suggested that I replace the 3 coil to plug connectors- I am finding out here on this forum that this is one of the least expensive things to check and should have been done early on. I will try this- followed next by the OVP as Mr. Dalton suggests.

By the way, the vacuum leaks and frayed wires on the engine harness were apparently caused by mice. I have been told to sprinkle whole cloves in and around the engine compartment, floor mats and trunk. The smell of this spice irritates rodents and will keep them out.



If these two things don't solve the problem then it's time to say goodbye to this car.