One problem related to automatic transmission has been reported for the 2003 Mazda Protege. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Mazda Protege based on all problems reported for the 2003 Protege.
Under low acceleration between 1st and 2nd and between 2nd and 3rd gears there is a very low frequency noise that sounds like it is generated by a vibration. This has happened since the car was purchased new. I have had it in twice for repair to no avail and the dealer refuses to keep the car overnight to investigate the issue further.