My check engine light came on today as I was coming home for lunch, truck runs but power way down, not noticed any change in exhaust smoke, amp / oil / temp / fp all OK. I think there was a thread started about the same thing over at TDR yesterday but TDR forum is down right now due to worm. What should I check first, I’m thinking someone mentioned the intake air temp sensor ???

 

Nevermind, found it, IAT unplugged.