yesterday, my 94 gt started acting really gay. i would be driving it around and it would just die. after it dies, it's really hard to start back up and i had to push it off to the side of the road this morning and like 5 minutes later, it started right up. anyone know what would cause this? only mods are k&n and american thunder mufflers(both came with the car). any help with this would be greatly appreciated.