You have a faulty range sensor on your 4L30E tranny. It's bolted to the shift arm that sticks out the left side side of the tranny/ drivers side floor area. Really easy to remove & replace (it's like a $175 part). Per Keith- an isuzu tech on several isuzu sites, you can remove the sensor & clean the contacts. Try the dealer first- will be covered if you still have 3yr/50Kmi b/b warranty left. G/luck
Joel
Joel
