My 2004 coupe has decided to upshift to OD (5th) at slower speeds (35MPH and less). Cant' seem to find a good dealer here to get a code (none of the techs know crossfires). During warm up it shifts normally, then gets a noticeable "bump" while shifting up. It has even shifted into OD while stopping, causing the motor to die. Perhaps on another subject (?), my spoiler now stays deployed full time???