My truck had a gas cap error for a few months. It was getting close to tag time and I needed to fix it.

And wanted to say that those $80 smoke machines on Amazon work wonders. That thing probably saved me a $1000 shop ripoff repair.

I found a hole on the EVAP tube over the gas tank that looks like a critter bit into. Taped over the hole then gooped it all up with epoxy for a permanent seal. A few restarts later the code is gone.

 

Awesome fix! Love seeing an at home repair work so well!