I was driving down the highway the other day in my 06 SCab 5.4 and all of a sudden, the Check Fuel Cap message pops up on my display. Now I had about 160miles already on that tank of gas before the message popped up and at the next stop, I checked the cap and it was fine. I have filled the tank up since then and continue getting the message. I figured the system might have to reset itself after a few starts but it has been 3 days and 10+ starts later and I still am getting the message. This is a stock fuel cap any suggestions??

 

Ive had that feature on my last few trucks and have yet to see it. Check to see if there is any debris around the cap that may be setting off a sensor that the cap isn't on.

 

The sensor is in the evap system, it can't pull a vacuum in the tank.

 

now would the lack of a vacuum in the tank mess up the truck? because it seems to run no different

 

I tried an aftermarket locking gas cap on my '05, and on first start, the light went off. Took it back and the counter guy said the light would go back off after approx 50 starts. He was right.

 

Opps sorrry