Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Have you by any chance replaced the ignition module?
Ok double check the shaft that the rotor goes on for excessive play. This would cause a misfire issue.
Yes the coil can also cause this issue. The coil gets its signal of when to fire from module.
Any new info?
Do you have access to the gm scanner? If so check fuel trims when its acting up. If its running rich you should check injector assembly for leaks. Another thing to check would be misfire counts with the scanner. Depending on what cylinders are misfiring, it can point us in a better direction on what to test.