Arnage 4.4 Misfire Mystery

[EdwardC]

From time to time under full throttle from standstill, my Arnage is misfiring on cylinders 2 and 8. Today I had all the spark plugs changed as I was getting fed up of the 'check engine' light coming on and the car going into limp home mode. At the same time, the garage switched the coils around and yet the misfire still occurred on cylinders 2 and 8. Therefore the problem can't be plugs or coils.

Is the problem likely to an issue with the ECU, problems with the wiring between ECU and the coils or perhaps a crank shaft censor? Another garage I use from time to time has a 4.4ltr in at the moment. Can the ECUs be swapped between the two cars to see if this solves the problem or do they control the alarm/immobiliser as well?

[andypocock]

It shouldn't be difficult to track down if you can replicate the fault with a dealer level scanner attached.

Add knock sensors to your list of possibles.

Andy