would an engine misfire throw a check engine light?
Thread Starter
Super Member
Joined: Nov 2002
Posts: 766
Likes: 1
From: San Francisco
CLk320
would an engine misfire throw a check engine light?
I brought my car in for a transmission flush, brake change, and replacement motor mounts (a bit of a vibration when idling). The shop tells me that besides from the motor mounts being a bit worn I have a misfire on one of the cylinders. Not only do my motor mounts need to be replace but I would also have to replace some wires and coils...I'm thinking wouldn't that throw a check engine light, which never did. Can anyone enlighten me on this subject? Thanks.
-Greg
-Greg
Last edited by 3 bAn 2 PoW 0; Mar 28, 2008 at 10:27 AM.
MBWorld Fanatic!
Joined: Apr 2005
Posts: 3,784
Likes: 84
From: SCV SoCal
2002 CLK430
A misfire can cause the CEL to illuminate. Usually it's a bad wire or a coil. Several bad wires usually means the wires are just worn out and should be replaced. I've never had multiple coils go bad at the same time. That sounds somewhat unusual.
Thread Starter
Super Member
Joined: Nov 2002
Posts: 766
Likes: 1
From: San Francisco
CLk320
thats what I was thinking too...wouldn't a misfire on the engine mean I would lose significant power? I've never felt a loss in power with the car. I still don't see how would rough idle would be caused by a misfire by of the cylinders. The only thing I could think of that would cause a rough idle would probably be the motor mounts... any other suggestion would be a great help. Thanks.
Senior Member
Joined: Sep 2006
Posts: 303
Likes: 0
From: NorCal
BMW
I experienced 3 cylinders misfiring last summer. My check engine light was always on and when I felt the misfiring, my check engine light would blink for about a minute and become solid till the next misfire.
I experienced a huge loss of power esp. when the car was cold. I had mornings when I could barely get past 25mph and had to pull off the road to let other cars pass.
I replaced the drivers side motor mount and all problems were solved..
I experienced a huge loss of power esp. when the car was cold. I had mornings when I could barely get past 25mph and had to pull off the road to let other cars pass.
I replaced the drivers side motor mount and all problems were solved..
MBWorld Fanatic!
Joined: Mar 2008
Posts: 1,753
Likes: 2
From: New York City
Yo Momma
your car can be misfiring and you will not notice it, the check engine will not come on, it can be a slight misfire but not strong enough to reduce power or give the check engine light. Take it to another mechanic and see what they say. Always get 2nd opinion. I also notice a slight vibration at idling, is it the motor mounts 100%?
Newbie
Joined: Jul 2005
Posts: 5
Likes: 0
I was told that the coils rarely go bad. I had that issue over a year ago and replaced 3 wires (did'nt feel like replacing 16)... worked fine after that... and yes, it will cause the check engine light to come on.
Last edited by tbsi430; Mar 31, 2008 at 04:03 PM.
