My "Service Engine Soon light" came on the other day, and when I went to get gas I found that the gas cap was totally off (no idea how that happened). Would the gas cap being off cause the light to come on? If so, how do I get it to go off? The car had just been in for routine service a couple of weeks earlier.

 

yes it will throw some kind of evap system code..
simply tighten it back up and follow the ecu ressetting
without diconecting batt cables found in the diy section

 

OR - I believe it will simply turn itself off after X number of starts. I forget the value of X - something like 20ish? Of course - the gas cap has to be on and tight

Use to happen to me when I lived in NJ - couldn't pump my own gas there (not allowed) - kids occasionally forgot to put it back on - drove me nuts.

Good Luck...

 

Hey thanks for the replies. The light did go off by itself as Malbec said, not sure how many starts it took.

I think I'll still try the ECU reset thing though and see what effect it has,sounds interesting.

Thanks again.