Nikki3721

Did you figure out the issue? I have the same code and symptoms in my ‘15 Sierra. Just purchased cats and o2 sensors to change out once weather clears, just really hoping it’s related to those. I did not previously have any codes, but a bad rattle and exhaust fumes coming in the cab.

Actually very common. This happened to me in my 2015 more than once. Under warranty and I still had to fight with GM tirelessly about it. A total nightmare. So unfortunately I doubt you’ll get them to put for any of it. If you keep it I would definitely get a AFM disabler. and to be honest, if I could do it all over again I would have dumped the truck then. That problem lead to other big issues that I also had to fight with GM and the dealership about. When I picked the truck up I made it 14 miles before it popped, went into limp mode and started puking fuel into the crank case. Towed back. Didn’t pick it up for 6 weeks as the “largest dealer in the Midwest” repaired a completely different pet than what I was told when I approved the repair (fuel injector pump, which it was, vs the fuel pump, which obviously it was not) made it 22 miles that time before I was once again stuck on the side of the road. There’s more, but I think you get my point. Unfortunately my financial situation has dramatically changed so I’m stuck with the truck for now. But I will NEVER buy another GM vehicle after this one. Complete $hit show.