Check engine light came on. Test at parts store gave code of P0455. Checked canister and vacuum lines - OK. After last fill up I parked it in the garage and there was a strong odor of gas until next morning, light came on two days later. Can you tell me what the problem is?
P0455 Evaporative Emission Control System Leak Detected (gross leak)
Start with the gas cap. Be sure it's tight. Large leaks can often be found visually. Look for a cracked or disconnected hose, a loose or rusted-off hose clamp, ... Things like that. If you can't find anything obvious, your mechanic will use a smoke machine to inject a white, non-toxic smoke into the system, then he will look for where it sneaks out.