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1996 SE, Auto trans. When driving up hill (not a big hill) more of an incline the overdrive pops in/out of gear when trying to mantain a constant speed. It drives fine other wise. To make it stop I just drop it down into "D" or third gear. Also in the mornings I can hear the clutch packs make their switch from 2nd to 3rd gear. Trans has never been service. Just wondering if this sounds more bad like transmission failure about to happen or would serivceing the trans fix or help.

After your normal commute, what does the trans fluid look or smell like? Taste if you like too!

Sounds like too many rpm's of slip detected in the TC, and unlocking would be the PCM's method of protection. Based on your fluid autopsy, we may suggest a pan drop and filter change, plus an external cooler.

EDIT:

Just saw your sig. Describe the modified TPS. This may also be a factor in kicking the OD out.

willwren wrote:After your normal commute, what does the trans fluid look or smell like? Taste if you like too!

Sounds like too many rpm's of slip detected in the TC, and unlocking would be the PCM's method of protection. Based on your fluid autopsy, we may suggest a pan drop and filter change, plus an external cooler.

EDIT:

Just saw your sig. Describe the modified TPS. This may also be a factor in kicking the OD out.

It is a quick mod which allows you to take advantage of true full throttle. You take the TPS and drill out the mounting holes so they are oversize. Then skin the connecting wires back so you can get to the bare wire of the connector. Remount the TPS to the engine. Turn the key to on/run. With a volt meter measure the volts to the TPS. You want to get as close as possible to 4.3volts (not sure if the volts is right, will have to look it back up). Tighten the screws down and spring the TPS to make sure you still are getting the same reading. Start the car. It will take about two times starting and running for the PCM to learn the new input. After I first did this tune I was able to do a 25' to 50' burn-out.... smoking both tires from a dead straight luanch. Thats NO supercharger stock SE! The car is wicked fast and has been driving and shifting fine up and till now. Its been about 4yrs since I did this mod to the TPS.
Trans fuild is dark and smells a little burned.like this.

Your OD is over-sensitive to TPS inputs now.

Set it back to stock, or at least half way. Please take a look at your trans fluid as I detailed in my reply above.

Dark Fluid = Bad. Do a pan drop and replace the filter, drive for a week, then do it again. This will get 90%+ new fluid in your trans.

Your TPS mod sounds a little ricer TBH. What you should've done instead was use a scanner to detect if the sensor was reading 100% throttle when your foot was to the floor. If not, then would've been the time to adjust. Your PCM cannot interpret inputs over 100%, it just treats them like 100%, from what I understand. Basically you've just made it so that it takes less pressure on the pedal to get more throttle, which actually probably has you running a little rich, because the Computer thinks the blade is open 50% when it's only open 45% or whatever, and it's adding too much fuel compared to the air that's coming in.

It does not cuase it to run any richer. It just take into account the throttle is really wide open when you hit the floor. Its like advanceing you dewell in the old days with point igintion. And your right it doesn't take much foot presure to open the throttle. Before the engine would ever go past 5k rpm. Now you have to watch the tach cause you can redline very easy. The PCM reaches the power curve at a much earlier rpm, thus more power to the wheels at 5k rpm. Gas mileage is the same as it was before stock settings. Your just advancing the power curve.

Your TPS input is used to unlock the TCC. It has a direct impact on your transmission, particularly overdrive. Set it back to stock and drop your pan.