Taking it to get it checked tomorrow, but I haven't noticed anything funny w/ the car. It came on last night and didn't notice anything durring that drive. Drove to work today(almost 100mi round trip) w/ no issue.

Cap is tight, cruise is fine, all instruments functional. WTH?

EDIT: BTW, 2005 AWD 3.0 Sport A/T.

 

It could be any number of things that won't immediately affect how it runs. For example, an air leak in the intake system or a Mass Airflow Sensor needing cleaned.

 

Dude 9/10 its a vac leak. Check your vacuum hoses and if nothing its your IMT o-rings. Either way, cheap fix. Look around and get back to us.

Vacuum leaks are the only things that are finicky like that. Happens ALL the time. And the one that creeps up like a ninja is the IMT o-rings, which by the way are located on the passenger side of the intake. Two black circular discs. Just inside are o-rings and they dry up and crack causing a minute leak just enough to send the CEL off then run normal again.

 

Bingo. It's the rings - cracked like Courtney Love. Getting replacements today @ AC Imports. Thanks so much!

 

Lmao-Courtney. Good deal.