Hello. I'm looking for some help. I've owned several chevy and gmc vehicles. From 97 gmc yukon suburban, 2006 trailblazer ss, 2012 silverado, and i have a 2008 sierra. Last week i was up in Canada and had temperatures between -20 and -40. It was terrible lol. On my way home my check engine light started flashing and my stabilitrack light came on. I was about an hour and a half from home when this happened. I always carry a code reader in the truck so i checked the codes and it was p0449 and p0301. I changed the vapor purge valve and the evap canister solenoid and it took care of the 449 code. Then i swapped the spark plug, plug wire, then coil pack from cylinder 1 to cylinder 3 and it still showed cylinder 1 misfire. So i changed the fuel injector and it still showed p0301. The spark plug from cylinder 1 definitely had gas on it and was kind of black with a build up on it but didn't look like carbon or oil. The truck kinda stutters and idles rough especially when i put it in gear. I appreciate any help.
