checked codes once again, and all it shows is code for battery disconnect, and completion of test. i believe its codes 12 and 55, but not sure. yesterday we decided to try overdrive again, and it ran just fine. did check coil with meter, and two towers were lower than other 4. will try new coil, it cant hurt. did check EGR, and stem seems to be moving fine. Thanks for the ideas!! we will figure it out sooner or later.