Have a 2018 5.0, 12,000 miles. Today a check engine light came on and stayed on for a 60 mile drive. On the way home " check engine light still on ) I stopped for lunch and after lunch the light is now off. Any thoughts?

 

C'mon....how is anybody suppose to diagnose that????? Take it in.

 

Go to one of the big Auto parts stores and borrow their OBDII reader and you can get the code right off the truck.

 

The only instance I know about CELs turning off by themselves is when gas cap is not seated properly then reinstalled... but our trucks don't have a gas cap. Like suggested above, just get the code with an OBDII reader and you'll know what it is. Most likely it'll require a visit to a dealer, but could be something stupid, especially if you did something to your truck recently involving electrical connectors. Good luck.

 

Duh, truck was obviously hungry.

 

The OBD system saw a fault and turned on the check engine light. If the system didn't detect the fault again in a pre-determined number of cycles,
it extinguishes the CEL.