M104 C280 High RPM engine misfire
Just discovered a strange misfire situation in my 94 C280...while in park, I slowly revved the engine up in rpm and all was smooth as silk until reaching 4,000 rpm, and then it started a consistent hard miss at 4,000 and above. Was able to repeat this every time I tried to go past 4,000 rpm. Then took it on the road and strangely it does NOT seem to misfire at or above 4,000 rpm while driving. Drove around for a while and could not get it to miss while driving. Brought it back home, put it in park, revved up and it STILL misses only at/above 4,000+ while in park!
Put a significant amount of work in car within the last year with only OEM parts from the MB Classic Center including- complete engine wiring harness, all six spark plugs, plug wires, boots, spark plug wire connectors, cam position sensor, crank position sensor, cam magnetic position sensor, OVP relay, valve cover gasket and motor mounts.
I've read about a high rpm 4,000+ misfire situation when the car is IN GEAR that is due to a transmission overload protection switch, but that seems not to apply to my situation...
Any suggestions?
J.G.
|