C5 Misfire
Thread Starter
2nd Gear
Joined: Jun 2014
Posts: 2
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C5 Misfire
I have a PO300 Misfire Diagnostic Code in my 2002. Should I just I just change the plugs and wires or is there something else to check first? Check engine light blinks. Idling really rough, just got it out from winter storage.
Le Mans Master
Joined: Sep 2013
Posts: 8,900
Likes: 1,074
From: Wisconsin
How was it stored and for how long? Was it running good when you put it away?
Team Owner
Joined: May 2001
Posts: 36,836
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Good question. One of the first things I'd be looking at would be fuel injector and/or coil wiring harnesses for signs of little meece-teeth.
Le Mans Master
Joined: Sep 2013
Posts: 8,900
Likes: 1,074
From: Wisconsin
If it was running fine when he put it away, something must have happened during storage. Maybe bad gas or moisture, low battery or like you said mice.
Melting Slicks
Joined: Dec 2000
Posts: 3,279
Likes: 1,097
From: Pittsburgh PA
Could be something like stated above. In my case the car was new, it would through a miss fire code a couple times a year. The car ran real good. After 14 years it started to run ruff. Pulled the plugs and one was fouled from the factory, the gap was bad. New wires and plugs runs great.
Last edited by Fcar 98; Jun 30, 2014 at 08:25 PM.
Melting Slicks
Joined: Jul 2012
Posts: 2,507
Likes: 9
Get a different scanner on it, the DIC doesn't show specific cylinders. If your car is a Z06, you might want to check the valve springs too, they break on the Z's and if you don't catch it, it ain't pretty.
Last edited by 3boystoys; Jul 1, 2014 at 09:35 AM.
