M275 Idle misfire (or return to idle misfire)
Thread Starter
Member
Joined: Jul 2019
Posts: 122
Likes: 41
2007 CL600
M275 Idle misfire (or return to idle misfire)
Hi all,
Does anyone know what can cause a misfire during idle only, or that can be provoked by poking the throttle pedal and letting the car roll back to idle (it then stumbles a bit when it hits idle rpm).
Codes aren't being set but they can be felt, and are detected by the fault counter. One cylinder (nr. 5) is notably worse than other but it occurs across about 9-10 cylinders. Cylinder 5 has read up to 5 faults on the counter before it resets.
When being driven under any conditions there is nothing registered on the fault counter under any driving style. This only happens at idle.
Any ideas?
Does anyone know what can cause a misfire during idle only, or that can be provoked by poking the throttle pedal and letting the car roll back to idle (it then stumbles a bit when it hits idle rpm).
Codes aren't being set but they can be felt, and are detected by the fault counter. One cylinder (nr. 5) is notably worse than other but it occurs across about 9-10 cylinders. Cylinder 5 has read up to 5 faults on the counter before it resets.
When being driven under any conditions there is nothing registered on the fault counter under any driving style. This only happens at idle.
Any ideas?
Thread Starter
Member
Joined: Jul 2019
Posts: 122
Likes: 41
2007 CL600
Well I'm pretty astonished. Reinstalled the original style throttle body gasket and the misfire on cylinder 5 has gone. Nothing looked wrong with the "updated" throttle body gasket when I pulled it off. It seems that perhaps the M275 gasket being smaller than the throttle body opening has some significance.
