I changed my plugs a short while ago due to a very bad misfire on cylinder #6. the new AC Delco plugs fixed the rough idle and misfire....for about 3 weeks. I was sitting in a drive-thru when the miss returned. now after another 3 weeks today it finally set a CE light, I pulled the code when I...

My 2003 TB all of the sudden started running bad at a stoplight. Check engine light flashed and then came on steady. Checked code when I arrived home. P0306, misfire cylinder 6. After going through the forum I decided to swap ignition coil 2 and 6 to see if the problem would move to cylinder 2...

I have an 03 Trailblazer LS with 107,000 miles on it and yesterday one of the cylinders starts misfiring (blinking "Service engine soon" light). The truck struggles to idle properly and there is obvious hesitation during acceleration. This seems to start after it's been running for about 5...