Low modulating pressure...

[filon102]

I finally managed to put my auto trans back together after a long year rebuild... but im having a bit of an issue. Car goes forward and backwards, but it requires A LOT of gas. So I checked trans fluid 1st, was a bit low so I added more, dint help.

So I got under the car, and installed oil pressure gauge on the modulating pressure port and pulled off vacuum line to modulator. Started the car up and Im getting 18psi in park on idle, when I put it to drive, I get only 14ish. Specs requires 4 bar or 58psi. I tried adjusting the modulator valve on the side of the trans, pressure did not rise but it fell when I back off of it.

Since I had alldata account, I managed to see a TSB regarding "Slipping or Soft Shifts":

To inspect for this condition, remove the modulator. Start the engine and press in on the modulator valve assembly (figure one). If there is now pressure showing on the pressure gauge, make a shim and install it into the modulator valve (figure two).

I did that and the pressure did not rise when I pressed in, so Im really running of ideas of what it could be. Ill probably check working pressure next, but my guess it is fine since I installed new front pump...