I just had somthing happen. I was starting it cold and it was doing it's usual thing sputtering up to where I could get it to idle while holding my foot on the gas... and then somthing "clicked" under the hood and the idle smoothed out and shot up to about 1000 RPM, like it's suppose to be. I think at that exact moment the Check engine light flashed on then went off. The "click" sounded like it came from the passenger side of the engine compartment.

Any ideas what this could be?