help ! Gas door opens when driving

sounds like the "hinge" has gone loose. There are "replacment" billet units, and the door unbolts check it out, a junk yard would have a replacment or any 4x4 shop will have one the expensive billet racer type replacments.

I had the same issue on a 91, I glued a magnet to the opening so the "door" would stickl to it when closed. Didnt work to hot on bumpy dirt but free way and stop signs 100%

Duct tape!