Misfire under WOT Help diagnosing
 

Hey guys picked up a 2005 CL 55 AMG, only issue is that it Misfires under WOT, if I drive normally there no misfires no CEL and car drives effortlessly, but If I stand on it about 4k rpm is starts to pop and misfire, ive hooked it up to my friends STAR tool and it said there was a misfire on cylinder 1 and 2 so I replaced both coil packs, its better but still misfiring under WOT, any ideas? thinking plugs and wires next.

Thanks for the help :y

sounds like you are on the right track. plugs for sure and you can swap the wires too for diagnosis purposes.

I am also having a misfire at WOT in my E-55.

Cylinder #4. Swapped coils for different cylinders. Gave it a coil, 16 plugs, wires... No change.

Fixed vacuum leaks at plenum box for passenger side and did the rest of intake gaskets as the supercharger was off.

Injector has same resistance as the other cylinders. 26.5 ohms if failing memory serves.

Have not swapped injectors with another cylinder. Worth the effort? Idles and runs well aside from WOT.

May have seen a change once while wiggling engine wiring harness. Not certain and am unable to duplicate that.

Are any of you aware of a pattern failure in engine harness or ECU?

Thanks!

wrong thread

Wrong thread too, sorry