I own a 90 eclipse 1.8L. Was driving on the interstate and all of a sudden it shifted down then back up 2-3 times and then finally shifted back down to 2nd and stayed there. Took it straight to the chysler dealer (no mitsu dealer) shut it off and when they tried to get it to do this it wouldn't. They finally have gotten it to do this but have not come up with an answer as to why. As far as I know, it is not putting out any codes. The dealer has had it about a month and are somewhat reluctant to tear into it because of the cost. Anyone have any ideas as to what it could be? Any help would be appreciated. Thanks

 

transmission control module could be on the fritz, or your fluid might be overheating,high temperatures can cause that.
check the level and make sure its good red fluid, not burnt up brown colored.