my cars been sitting for several months now, waiting on parts and my procrastination. i just realized my tank is full. now i know they sell a gas stabilizer for things that are rarely driven, like boats but i didnt have the foresight to use that. so how long does gas last? if it is bad, would an octane booster help? i'd hate to get my car running again only to blow the motor the first time i boost becuase of something stupid like old gas.