I got a 2017 SIlverado 5.3L V8. Got it in January, and around April or so I had a misfire. Brought it to dealer and they switched coils around and stopped misfiring. Misfired again month or so later so got all my plugs replaced. Didnt work and also got CEL for EVAP so replaced all the EVAP stuff and it misfired again few weeks later. Threw Sea Foam through it and into the fuel as well. Misfired again few days later. Its popping up as a random misfire and it only happens on the highway (around 70 MPH or so). Not sure where to look to fix next. Bringing it back to dealer but also dont want them to say they cant recreate the misfire and dont know what to do. Was thinking maybe bad wire, coil, o2 sensor, maf, or crankshaft sensor. I guess it could be fuel injector too but not sure. Anyone else have this kind of misfire wild goose chase?
