I was hoping to get help with some questions about my 94 diamante LS. It has been having intermittent shifting problems...first problem was that it would not go into overdrive, sometimes remediable by stopping car and turning off engine, then starting. Another symptom: sudden, very jarring downshift into first gear. often car will stay in first or second gear. other times works normally. Does this sound like PCU/TCM? i did the diagnostic where you ground pin one and check engine flashes--got normal reading. any help would be appreciated, jim

 

when was the last time you had the transmission flushed? These types of symptoms generally point to a bad transmission