Engine Performance problem
2001 GMC Yukon 6 cyl All Wheel Drive Automatic 130K miles
I have an intermittent problem that has been driving me nuts. I can sometimes just start the engine and it starts rough ( misfires) or drive up to 50 plus miles with it running smooth, before I receive engine code P0301 - Cylinder #1 misfire. I have replaced the following over the course of 6 months ever since it did not pass emission testing from the service engine soon lamp.
1. Cylinder #1 coil pack.
2. Plug wires had only 15K miles on them, so I swapped out cylinder #1 wires with another cylinder, the trouble did not follow.
3. Replaced both O2 sensors, upstream and downstream on bank one side ( drivers side of engine).
4. Paid to have injector cleaner fed directly into the fuel rails along with a gas tank injector chemical.
Recapping, this is an intermittent problem, maybe 60-70% of the time the engine is driving rough. I have a decent error code scanner that provides lots of information. I can clear the error code and wait for it to come back.
Any ideas before I start going back and re checking / changing all the above again?
have the same problem?
Friday, August 6th, 2010 AT 10:29 AM