Join Date: Jun 2008
Location: Mercer Island, WA
2007 OR Xterra
Remember, the check engine light only comes on when your emissions are not regular. This is why when your gas cap is screwed in wrong, the light comes on. Note: That the engine light will continue to be on, even after you fix the gas cap. Mine didn't go off till I drove around 30 miles.
I also had the light turn on after I installed a new intake. The air calibration sensor came undone. You may want to check that as well.