2000 Mazda protege won't shift into 4th gear(automatic]
Asked by Adam Jan 25, 2023 at 11:46 PM about the 2000 Mazda Protege
Question type: Maintenance & Repair
My little pos car. It won't shift in to 4th gear, but
here's the part that gets me. When it hits over
2500rpms the battery light comes on and the air
bag light flashes 3 times pause and then 3 more
times. Do I need a new transmission and the wiring
checked or just the new transmission
7 Answers
Sounds like voltage issues, could be a failing alternator or slipping drive belts. The computer needs a stable voltage to make things work right, if voltage is too low to the sensors it could cause shifting problems due to the computer getting inaccurate readings. I would get the vehicle live data scanned to see what is actually cause the problems. Now it could be a transmission or even a valve body problem but you need to make sure everything else is operating properly.
New alternator. It's been shifting hard and iratic shifting for a while.
Just cause it’s new doesn’t mean it’s a good one, one little ripple in a diode or a flying open and things go nuts. When was the transmission serviced? Could be a plugged filter.
Did a fluid and filter change a week ago when it first lost 4th gear
I would still get a live data scan. If nothing shows there then got to a good transmission shop so they can do stand alone testing, that will determine if it is the transmission or an electronic solenoid or valve body.
Yep already done. New battery terminals, ran a voltage test and everything came out OK. I'm completely stumped. Grounds are cleaned and tight, found no breaks in wires. Wtf