Toyota Repair: 0440 & 0442, negative battery cable, emission control system

Question
Hello,
My check engine light came on so I checked the code and it was 0440 & 0442, when I looked up these codes I found that it is an "Evaporative Emission Control System" malfunction and that a small leak is detected. How serious is this? Do I need to give this immediate attention? Thanks for the help.

Andrew

Answer
Not real serious, it just means that there is a small leak in the fuel vapor recovery system, it will not affect driveability, most of the time it can be caused by a loose gas cap so make sure the gas cap is tight or just try replacing it for a quick fix, remove the negative battery cable for ten seconds to clear the DTC then see what happens. If the light turns back on it's a little more complicated and the leak has tobe located with special detection equipment at the toyota dealer, keep in mind that most emission control related issues are covered under the federal emission control warranty(in the US) for 3yrs/50,000 miles and some are covered for 8yrs/80,000 miles depending on what model it is.