G60 Automatic Transmission blues!!

Purchased a 91 Corrado with the automatic trans in limp mode. So far I have replaced the tranny computer twice (2 used ones), replaced the solenoid wiring harness, checked continuity from there to the computer, cleared all computer codes (positive & negative together with key on) and basically checked all the connections and terminals for corrosion. Still in limp mode! Running out of ideas and places to look. I was told that the engine ecm can have "hard codes" that may effect the trans computer, not sure how true that is. I could really use some help here if anyone has been through this before. Let me know and thanks. 616-890-1475 Steve

try pulling ecm fuse in fusebox leave out a minute put back in try,if this dont work i soy good trans shop,possability a bad on board computer.