The evaporative emission control system (EVAP) prevents the escaping of gasoline vapors from the fuel system into the atmosphere. It redirects the vapors to a charcoal canister and then to an engine ...

Some 2005-09 Scion tC models may turn on the check engine light and store one or more EVAP system trouble codes in computer memory.

A check engine light, even if the car runs fine, often indicates a leak in the evaporative emission control (EVAP) system.

Faulty vacuum hoses at EVAP system: Loose hoses mean evaporating fuel will not reach its vented destination. That sets off alarms, or at least your check engine light.

Your check engine light can come on for a lot of different reasons, but there are only a few that occur after putting in gas. Here's what we know.

A check-engine light comes on after a fill-up, then goes away a few days later depending how many times I drive. Next fill-up, same problem. I make sure the gas cap is on tight. – B.M.