I just had a new alternator and passenger side exhaust manifold installed yesterday. I was driving the X all day afterwards and it was fine. I started to drive it this afternoon and noticed while at idle the Rpm's were only at about 450-500. This is causing it to try to stall and now the check engine light is on. I'm thinking that the serpentine belt might be to tight. anyone else have any ideas???

finding out what codes the ecu is throwing would be a great start, itd prob answer your question
go to an autoparts store nd tell them to scan it for you
what you describe sounds like it could be the prob, but knowing why your CEL is on should be your first step.

keep us in the loop

I'll let you know, I'll try advance auto parts tomorrow.

yes plz keep us in the loop....

OK just got the X from the shop. There was a blown fuse to the throttle position sensor. runs like a champ now.