Just wanted to know if anyone else around here received one on their 04. Got mine yesterday shortly after my first fillup. I am thinking it is the gas cap. This happened to me once on my wife's focus. The gas cap was replaced and the light went away. I do not have a scanner but I am thinking this is what it is. I do have an airaid cai but it was on for a couple hundred miles before the light came on.

 

could have been as simple as a misfire.

1 cyl misfired once and now you have a fault code.

Go to PartsSource or one of those guys that have a scanner to look up what the fault code is. It could just need a reset.

 

well I decided just to take the neg battery cable off and let the computer reset. No problems since I did that. Hopefully it was something non important.

 

yes that will reset it, but now you have no idea why you generated a fault code.


I would have been a better idea to find out what happened to generrate the "check engine" so you will know in future that something could go wrong.