I have a 96 Bonnie with 180K miles and the transmission won't shift into O/D until about 60 mph and then it is very touchy. The slightest change in speed and it jumps right out of O/D. This is killing my MPG. Used to be 25/31 now it is about 17/22. In today'* gas market that is not good. Any help will be greatly appreciated.

For slipping or no 4th gear.

Low fluid level
Plugged filter
debris in the valve body assembly
Bad 4th gear clutch

I would suggest a filter and fluid change.

Actually this problem started shortly after a fluid - filter change. Maybe 500 miles or so. Ya think maybe a vacuum problem??

Did you do the fluid filter change? One thing that happens real easy is this part falls out. You need to make sure it goes back in right.

did you just have the fluid and filter changed or did you opt on the flush as well.
The flush is not always the best thing to do with a transmission with high miles.
Flushing it will remove old tarnish that the transmission actually needed to perform correctly over time.

Dan...........just a question..........what happens if the thermo element is not installed or installed incorrectly? What exactly does it do, whats its function? Reason for my question is that during my fluid/filter change it DID fall out and I mayu have reinstalled it upside down with the indentation in the plate facing down instead of up..............my tranny "seems" to be functioning fine tho..........

I believe it'* a 1 way valve.

The fluid change was done by my mechanic. I did not opt for the flush as I thought it seemed like a lot of cash at the time. One other thing that came up in another conversation was the TPS. Is this adjustable or just an electrical component that may be shot?

Thanks for the replies so far guys.

Nothing can be adjusted on the TPS. You can test it by using a ohm meter between the signal(dark blue) and the ground (black) Watch for smooth changes, no jumps. I think that'* what you need to do. Guess I should try it out. Looks like I'm doing another write up.

Here you go.



Locate your TPS, it'* on the throttle body in front. This is the sensor that'* connected to the butterfly inside the throttle body.

You will need to unplug the sensor.




Then using a ohm meter locate your sense wire, (Dark blue (center)) and your ground wire, (black(bottom)) and connect the meters probes to these. Alligator clips will make this much easier.


If you don not have a auto scaling meter you will need to set to the correct scale.


Now move the linkages and watch the readings. Move it slowly. You want to see a smooth change in the reading. Open all the way, then slowly close it again watching the readings. If at any point you see the readings drop or not move slowly, the sensor is bad.