OK, I am working with a 1997 S 320 with 63k. I went to Autozone, cause my Check Engine light was on and I have a very rough idle when sitting still. I had fault codes for misfire condition ( in cylinders number 5, 6, and random cylinders. So I changed the plugs, wires, MAF, and front Oxygen Sensor. The problem persists. What should I do next?
Did you change ignition coils with the wires? Are you still having misfirings?
Best regards
Hubert
__________________
300 SE, EZ 10/91, 97.000 km, Originalzustand, 4-Gang-Automatik, blau/schwarz, Leder schwarz, Sitzheizung, Klimaautomatik, ASD, Servoschließung, Schiebedach, Parameterlenkung, Becker Grand Prix, Mittelarmlehne mit Box, Wurzelholz, Colorverglasung, Einbruch- und Diebstahlwarnanlage o.I., 8-Loch LMs, Winterräder mit Originalabdeckung, original Feuerlöscher, abnehmbare Anhängerkupplung, komplette Dokumentation
OK, next step is do a compression test. As the readings were specific on 5 and 6 this would indicate problems with these cylinders. You have changed the only other items that can cause this.
OK, next step is do a compression test. As the readings were specific on 5 and 6 this would indicate problems with these cylinders. You have changed the only other items that can cause this.
I have a similar (maybe exact) problem.... How do you do this compression test?? Is it something I can do myself... without taking the car to the dealer?
Have you checked whether after all your changes you are still doing so? Hopefully yes as otherwise we are on an expensive track...
And if yes, look for the ignition ECU.
Best regards
Hubert
Hi Hubert, it seems that he has changed the coils and plugs for those cylinders and that did not cure the problem, thats why I suggested the compression test. The compression test is not a diy job, but almost any garage can do this and the result should be approx 12 bar percylinder. Any cylinder under 10 bar fails.
Idle Problems 
fault codes for misfire condition ( in cylinders number 5, 6, and random cylinders. So I changed the plugs, wires, MAF, and front Oxygen Sensor. The problem persists. What should I do next? 
Linear Mode
