Misfire at Idle and WOT above 4K RPM
Thread Starter
Junior Member
Joined: May 2008
Posts: 33
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2005-CL55, 2006-R350
Misfire at Idle and WOT above 4K RPM
I've searched and believe this to be a coil pack, but before ordering parts I thought I'd throw this out to see if I'm on the right track.
Last week, my car started stumbling/missing at idle. The stumble goes away the second you touch the accelerator and you cannot notice it at all when driving. It is very cold here, so I assumed an idle air valve issue. BUT last night, and today, I noticed that at wide open throttle I would also get a stumble/miss at higher RPM. I only did this twice, so as not to grenade a piston.
There are NO CODES, no CEL, no drive-ability issues, by the way. The fuel filter is less than 2,000 miles old and the plugs are about 15,000 miles old.
Any thoughts?
Last week, my car started stumbling/missing at idle. The stumble goes away the second you touch the accelerator and you cannot notice it at all when driving. It is very cold here, so I assumed an idle air valve issue. BUT last night, and today, I noticed that at wide open throttle I would also get a stumble/miss at higher RPM. I only did this twice, so as not to grenade a piston.
There are NO CODES, no CEL, no drive-ability issues, by the way. The fuel filter is less than 2,000 miles old and the plugs are about 15,000 miles old.
Any thoughts?
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From: Houston
2003 W211 E55, 2003 W220 S600
most of the time when you have a bad misfire a CEL will be generated.
if you are getting a vibration start checking your engine and transmission mounts
if you are getting a vibration start checking your engine and transmission mounts
Thread Starter
Junior Member
Joined: May 2008
Posts: 33
Likes: 4
2005-CL55, 2006-R350
Just checked again, no codes at all.
The mounts are new (as are the flex joints)... besides that isn't it.
It is a definite misfire but smooth as a baby from 1000-5000 RPM.
It must be ignition related.
The mounts are new (as are the flex joints)... besides that isn't it.
It is a definite misfire but smooth as a baby from 1000-5000 RPM.
It must be ignition related.
