Didnt know where to post this, because my truck isnt a superduty and sure isnt a fast ford vehicle... but it is a ford. I own a '98 Ranger 4x4 single cab short bed 5spd 3.0L v6. I changed the alternator this morning after it went yesterday, and about 15 minutes after while I was driving the check engine light came on. Now, I am at the bottom of my gas tank, and the manual says something about bad gas making this come on (being that I am a college student condensation may have come about in the last few weeks of not driving and leaving it close to empty) however, is this something that happens normally? Maybe something they reset at the garage. Im pretty sure I didn't mess anything up, it's certainly not a hard task. Any ideas?