So about a month ago I changed the spark plugs on my 2018 Tahoe Premier 5.3 4x2, 122k miles, had this truck for a little over a year now; I took a long drive to Tennessee and probably a week or so later I started to feel it stumble or stutter but there was no CEL.
A few days ago my wife and I were driving and she noticed the CEL was flashing for a few seconds then stopped; then flashed again then never came back on. Took it to AutoZone to see if the can find the codes or anything, and nada. Took it to a Jiffy Lube, and nada. They couldn’t find what it was. It hadn’t came back on since, until today I was about to make a decent trip to Kansas for work. Probably, about 100mi into the drive the CEL kept flashing, and it would not go into V4 and when I started braking it would “jolt” a bit.
any ideas? I’m basically chasing a misfire and maybe something else.
