will not move with the overdrive on
Sounds like the OD bands or the torque convertor has some issues. I think your due for a transmission rebuild or replacement. The tranmissions in the 626 weren't the best, so have a transmission expert diagnose your issue so you can get an estimate on the repair, if you want to keep the vehicle. Good Luck!
Search Mazda 626 Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Mazda 626 Experts