charlesb2003

2005 E320 M112 V6

I’ve got a misfire at idle, very noticeable as a lurch at low speeds and it shakes the whole car at stop lights. The weird thing is that there are no codes.

My suspicion is coils and/or wires because I’ve recently changed the MAF, fuel injectors, the whole intake manifold, and a bunch of vacuum hoses. About two years ago I replaced the crank position sensor, camshaft position sensor, and the spark plugs so that’s basically everything else that could cause a misfire right?

I’ve done about 50k miles on the iridium spark plugs, mostly highway. So the only thing that’s left are O2 sensors and the coils and wires. Just replaced the wires with some AutoZone wires and it’s kinda better but not fully and those wires were crap so I’m thinking change the coils and get the correct wires from FCP Euro after Christmas, but I just wish there was a code to confirm this diagnosis.

Any advice? Thanks and Merry Christmas!

Overheated

I've been told that bad motor mounts can cause rough idle misfire like issues.

charlesb2003

I replaced the engine mounts and transmission mount a little over a year ago so I know what that feels like and this is definitely a misfire. The engine sounds lopey and the car lurches at low speeds. Throwing it into neutral removes the lurching but the engine still sounds and feels lopey. Even the lights flicker at idle sometimes and there is a hesitation when accelerating when it's bad like that, but then other times it drives nearly normal.