the check engine light would come on after driving about five minutes and then turn of on its own. just had the 45k service so i took it to the dealer to complain. i suggested that it may be the EGR valve after reading the posts here, but i don't have the technical knowledge to attempt this myself.
the service rep told me not to believe the stuff i read online.

they replaced the EGR valve under warranty. he charged me an hours labor ($100) to clean it out saying it was really gummed up.

i didn't make him eat his words though.