When waather is warm I have to put in gas as slowly as possible. and it still shuts down.I called the dealer where I bought the car and they said they never heard of this problem that I probly needed a new gas tank? Now that the weather has wamed up I no longer have this problem. I thought when we started using unleaded gas they put in expansion tanks so no fumes would escape? could something like this be the problem?
Clarification is needed here. When you say “it still shuts down”, are you referring to the gas pump or the car’s engine? If you are referring to the engine, it should not be running while you fuel the car.
That being said, if the problem is that the gas pump is shutting off, the likely cause is a problem with the car’s evaporative emissions system. The most common way that this system is damaged is by continuing to squeeze more gas into the tank after the pump “clicks off” for the first time. Were you in the habit of doing this before the problem began?
My best guess is that you need to replace either one of the valves in the evaporative emissions system (a very quick and cheap repair on Subarus) or you need to replace the carbon canister that is the heart of the evap. emissions system. On many makes (Toyota comes to mind), replacing the carbon canister costs about $300.-$400.
Since your dealership appears to have no clue, I suggest that you take your car to a well-reputed independent mechanic for diagnosis and repair.