Intermittent Problems with Shifting

I’ve been having problems with my 1995 Mazda 626 Lx. (203,280 miles) When I get to about 25 mph while driving, my car will sometimes refuse to shift. Once I get over that speed, it’ll finally shift to the next gear, but then a blinking O/D off light will start blinking. I know that means possible transmission problems, but if I let the car go about ten miles and stop, the problem goes away. After that it’ll work fine. Any ideas with what might be causing this?

To help us help you, we need to know if there is any Diagnostic Trouble Code present in the Powertrain Control Module. So have the codes pulled and hopefully the PCM will have determined what it doesn’t like. A qualified transmission technician can use the freeze frame data (if the PCM is capable) to determine if the 3-4 shift was commanded but did not complete. That would probably show up as a gear ratio error DTC.

I assume you have checked the transmission fluid level, condition (smell), and color. Get back to us with more info and we will try to help.

You can try a fluid change and a new screen. If that doesn’t help, start looking for new car.