So I have a 2004 Chevy Silverado LLY Duramax. I forgot to plug it in last night and now it won’t stay running. It will turn over, run anywhere from 5 seconds to 30 seconds and shut back off. Occasionally it will kind of chop like it does when it’s cold. I have since plugged it in for 5 hours and still the same thing. I was told it was gummed up and was told to run diesel 911 through it. I put some in and cranked it over for about an hour so it should’ve gone through by now and still nothing. Any help would be greatly appreciated!! I am also throwing the code (P0642) and I’ve had it pop up before but it never actually affected anything and I even deleted the code and it just barely came back after a month or two. Thanks I’m advance!