Q: Car misfiring on cylinder three

asked by on March 22, 2016

My car started missing on cylinder three. I figured it was about to drop a valve seat, so I pulled the head and had valve seats replaced, machined, and new seals -- an overall head job. I put the head back on and started the engine. It started right up but still had a misfire in cylinder #3. I checked the compression on all cylinders 120 PSI +/- a pound. I checked the pulse to injector with tester and could see pulse on tester. Then I swapped injector two and injector three. There was no change in the misfire in three. I got new spark plugs, swapped two and three plug. There was no change in misfire. I checked the rocker arm swing, which seems average to others, and there were no engine codes and no engine light. I checked that the spark was getting to plug, and it had a very strong spark. No CEL or Error Codes.

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