vibration/misfire on cold start?
Thread Starter
Junior Member
Joined: Aug 2011
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07 CLK550, 07 Z4
vibration/misfire on cold start?
Anyone get a intermittent vibration / misfire on cold starts at idle?
M273, 2007 CLK550
Intermittent being once every few seconds perhaps. Goes away when driving. Doesn't seem to affect high RPM performance, so I don't think its bad gas?
M273, 2007 CLK550
Intermittent being once every few seconds perhaps. Goes away when driving. Doesn't seem to affect high RPM performance, so I don't think its bad gas?
Super Moderator
Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Some likely causes are, plugs, from not running in the self cleaning range sufficiently, an ignition coil, bad airbox to MAF seal leaving the MAF hunting to correct fuel trim, a vacuum leak or a throttle body actuator acting up. Some actuators chatter & require replacement. TB actuator trouble never shows up on a Star.
If this is mainly a town car that does too many short trips I would start with plugs. When last were they changed?
Good luck!
If this is mainly a town car that does too many short trips I would start with plugs. When last were they changed?
Good luck!
Senior Member
Joined: Mar 2012
Posts: 337
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JBs C63 PP( wifes car ), Mc Laren Pxx(toy), 2013 Mustang GT 5.0 ( DD ), ML 6.3 ( winter DD )...
Just do a small vid, load it up on youtube and then post it in here, maybe you dont have misfires, maybe your V8 just shakes a little because of wornout motor mounts....just do a lill vid of the enginebay so we can see and hear whats going on.
