Hi guys, we have this (203) c class which is really giving us grief and i am now asking for any help you may offer. It came in with an intermittant missfire and produces a p0301 code, initially changed plugs and after a few days replaced the coils as missfire was still present. We then carried out an extensive road test and witnessed the missfire as it pulled up to the workshop.it will continue to missfire until the engine is switched off,we then restarted it imedietly and the engine ran fine until several more miles were covered,then it will missfire when brought to idle. We have checked compressions and number 1 cyl is slightly lower than the other 3 but nothing i would consider too low. The injectors have been rotated to different cyls and the ECU has been repaired ( this did have a fault found under test ),have diconnected the wiring loome as best i can to check for any oil ingress, none found. If any one could shed some light my way it would be greatly appreciated, before i run out of hair
Many thanks Dave