Hi,
1996 Bonneville SE
244,000 miles

I searched the Techinfo and Forum posts and couldn't find an answer.

My transmission hesitates to shift into the next highest gear or when driving at the shift range it will sometimes feel like it slips back down and back up again. It'* not an engine issue. I apologize that I haven't been counting the gears to find out if it is one particular gear or if it'* just overdrive when it happens.

I do know the transmission has been replaced once. I was also going to do a full flush and filter change as I do not know the last time that was performed. Fluid level is OK.

Any thoughts?

I'll save somebody else asking. Have you had it scanned for codes?

since you don't know what gear its happening in, what speed is it hesitating at?

It hesitates right around 40mph. Maybe 35-40, somewhere around there.

I have not had it scanned for codes. The SES light has been on for years, that I know.

years? Get your codes checked before asking anymore questions.

OK,
Went to AAMCO this weekend and had the codes checked. This is what they found:
- Throttle Position Sensor
- Auxiliary Transmission Control
- Manufacturers Transmission Control
- Auxiliary Emissions

Any ideas or recommendation to go from here?

Well, starting at the top, the TPS has messed up my shift points on my 93 on a previous occassion. Felt like the tranny was going out.

You can do a voltage check at pin B (center) of TPS to ground w/TPS connected and key ON. These are specs for my 93:
Throttle Position Sensor (Closed Throttle) 0.33 to 0.46 Volts
Throttle Position Sensor (Full Throttle) 4.1 to 4.2 Volts

I also like to unplug it (ign. OFF) and do a resistance (ohms) check, center pin to ground and watch while moving throttle open and closed. A dial (analog) meter shows it the best. It should be gradual change with no "jumps." Also, at idle, should get almost no resistance.

By the way, my first replacement TPS, from AutoZ, only lasted 2-yrs and a few thousand miles. Have one from NAPA in there now.