Have a good tech pull the codes from the computer.

Mine would never straighten out and after I got rid of it I discovered the torque converter is a major problem in those trannies...

Someone makes a steel billet converter for it and everyone I have talked to who installed one, that ended the problems.

 Found out a day late and a few thousand dollars short....

The throttle body sensor on the fuel peddle interacts with it but that cured mine just before it went out again...

Pulled the battery cables off many times, pulled over and killed the ignition many many times so when I started back up the OD light would quit flashing and it would shift seemingly proper....

I would try the steel billet torque converter if I had it to do over again and I fought that thing from 93-04...

Someone on here I think from Kansas straightened me out, I think I have the post printed off and filed somewhere....

 Good Luck, I think you are going to need it!