The check engine light on my 04 Colorado recently came on and I had my service station run a diagnostic test and it came back with a misfire code. They didn't attempt a repair because there was a service bulletin from GM about the problem. It also said the exhaust valve springs and seals could be bad. I took it to a GM dealer and they ran a diagnostic to be sure and they came up with the same code. They recommended an injector and throttle body cleaning. They did their recommendations and they said after a test drive the same thing happened. Any thoughts?
SPONSORED LINKS
Tuesday, February 16th, 2010 AT 3:07 PM
1 Reply
DENNYP
MECHANIC
1,824 POSTS
Inspect the plug, coil, and boot on the problem cylinder. Do a cylinder leakdown test and a running compression test on all cylinders. This will show any leakage past the valves.