"Check Gas Cap" light is on

[Judeus]

For some reason my "check gas cap" light is on. I checked my gas cap and it's on there tight. What could the problem be?

[A.J.]

The 'check gas cap' warning is an emissions related message. It implies that the tank cannot be pressurized (slightly), therefore, the most probable cause is a loose gas cap.



You will sometimes get this message if the air temperature around the car changes greatly, and this results in a slight negative pressure in the fuel tank.



Winter weather can sometimes trigger this as well. Have you had a cold snap in your area recently?



You may also have to reset the warning light. There are two ways this can be done...one, use a OBD II scanner. (You can purchase these for as little as $20) or two, you can simply disconnect your battery, turn on the headlight switch for about five to ten minutes, and re-connect the battery. This is pretty simple, but will likely result in you losing your radio presets and perhaps some other small things like that.

[IAmTodd]

if the condition is corrected it will eventually go out by itself as well. I believe after 3 successful start ups it will disappear.