Mike It sounds like gears 1 and 2 are ok based on your note. Take the transmission fuse out (13) and this will cause the transmission to lock itself into 3rd gear. The transcomputer will be inoperative. It will be a little slow to take off but you will know if 3rd gear is ok. If it is then you can be 99 percent sure the transcomputer has done it thing to fail. Replace it or, you might call John Hervey. When I talked to him at the DMCH open house he told me he had rebuilt one which was now working fine. He had located replacements of the pieces that usually go bad. He might be able to help you out or repair it for you. Also, since it sounds like you are pretty handy in the fix-it department, you might want to check out the articles on the transcomputer repair on this web site. Harold McElraft - 3354