I have a 5 speed manual 1998 forester s that sputters out every time i drive it in the rain. My CEL has been on for a few months and the error reads evap. emissions error. The car seems to sputter out and the CEL always turns off when this happens. I usually can get the car started after 5 minutes or so but it dies as soon as i try to move it. I generally have to wait a day or two before it will run normally again. What do i need to buy to fix this?