I have a 2003 GMC Envoy automatic trans. i got obd2 codes cylinder 2 misfire and/or it will give random cylinder misfire codes. It runs rough with a puttering sound from the exhaust and a vibration you can feel from the seated potion. This car ran fine before i had a fuel pump replaced. I checked my fuel filter and ran some injector cleaner through the tank with about only 1/4 tank of gas. This has not helped. I put in new plugs and checked the coil packs all are good. Any other suggestions what to do. Also i should mention the car starts no issue and has good power considering the misfire. It seems to also run much smoother on some of our colder days than the warmer ones. Not sure if that info helps any. Thanks for any and all advice
if this all happened right after the fuel pump replacement odds are the job was botched either electronics to the pump or it set up right or it's the pump that doesn't work right. I only use the original equipment dental pumps myself. Not that was just a coincidence do my video fixing a misfiring engine Scotty
