mantycarguy

I maybe incorrectly assumed that he was getting 11 volts on the tps ground circuit. Since I dont know how he went about testing this, you could understand my response in thinking he had a short to b+ on the ground side of the tps. A simple voltage drop test with the tps unplugged would have confirmed circuit integrity.

mrvedit

Yes, that is my hypothesis.

A worn pump might be causing you to lose e.g. 30 psi. So when the PCM commands 50psi, you are getting only 20psi which is too low to run the trans. Once a sensor says the load is higher (or a sensor malfunctions) and the PCM commands a higher pressure, the trans works.

The only way to tell for sure is to hook up a pressure gauge to the trans. Any trans shop can do this for you and some might not even charge for it. They then plug in a scanner and command different pressures and see what the actual pressure is.

Sorry, but I do think there is something wrong with your trans because the PCM cannot command such a low pressure that the car will not move.
Again, this is only my hypothesis based on your descriptions and I could be wrong.

==> We assume you have checked the fluid level. You probably know this, but it has to be checked with the engine running.

98boxer

iTrader: (7)

You should check your transmission fluid oil level, but make sure you drive it at least 15 minutes and let it stand idle for a while than run through the gears and check fluid. I was having slipping problems into 1st gear and car would stop at a light having to restart car. Finally i did what i mentioned and i needed to add 1quart and 1/4 of quart and problem has been solved, i was having these problems after doing a transmission pan fluid change. Hope this helps.