While towing my 29' camper today we stopped for fuel and when re-entering the hwy, the CEL came on followed by service Stabilitrak, ESC, Parking Brake, followed by complete loss of power, and misfiring.

Got it off the hwy and towed to the local dealership, had OnStar scan it they came back with a P0300 code, we scanned it and got a permanent misfire on Cylinder 1.

Dealership is closed until Monday. Just wondering if this could be a failed lifter? Sounds more like a coil pack.

Truck has 88,000miles, I've owned it since new and have always had it serviced at the dealership.

I had no indication that something wasn't right prior to today.

 

I'd bet on a lifter and bent push rod.

 

bad coil pack and collasped lifter; both can cause a misfire. they will have to diagnose it.

 

I would say coil pack, fuel injector or spark plug. Most likely coil pack or fuel injector though.

 

I had a misfire come in one day. Come to find out, the plug wire had slipped off the coil. Pushed it back on and all was fine. Then, I looked up and read where there were problems with the wires slipping off the coils, as they are pointed down.