90&91max

My 91 w/automatic can't seem to decide if it wants to be in overdrive or not! On a slight grade at 55 to 65 it will constantly shift in and out of overdrive. If I let of the gas or give it more, it will stop for a while. I have a '90 parts car with a broke trans that I could use to swap out parts with. I just dont know what to swap! Thanks for your help!

smokyman13

There is a button on the shifter....make sure it is off and the light is on when you dont wanna feel the shift shocks of the tranny going from OD to a gear.....if it s off..the light is on...and it still does it......then maybe there are some worn bands in the tranny

DanNY

iTrader: (14)

when was the last time fluid was changed?
check to see if the fluid is low.

your TPS is ok right?

90&91max

Fluid was changed a few thousand miles ago. Not sure what the tps is? Throttle position switch? What effect does this have and how do you adjust it?
Thanks

DanNY

iTrader: (14)

ok then check fluid level...make sure it's at the right level.

throttle position sensor...it doesn't go bad much. but how much gas u give will determine if the car should downshift or not.

maximase86

iTrader: (24)

I wonder if the fluid level maybe overfilled? I had a similar problem on my 88 ranger. The fluid was overfilled and it caused it to have the same problem....but eventuually the overdrive stop working. I would check it ASAP if I were you.

S