Q: my gas cap keeps coming loose causing car to shut off. This only happens when its out side

This one makes me very curious. The car should continue to run whether the gas cap is loose or not. In fact, the car should be able to run with no gas cap at all, but the check engine light would come on. So I think the problems might not be related. It could be that the time you take to get out of the car, tighten the gas cap, and get back in to re-start the car may be all it needs to function again. There are many things that will make a car stall, then re-start after sitting for a couple of minutes. Still, it’s an intriguing problem. So I recommend you contact Your Mechanic and have a technician come out to your home or office to check out your stalling issue and possibly replace your gas cap.