90 LUMINA 3.1 trans. problem

[RCAID99]

it has more than 150,000 miles and it just wont shift out of first gear i unplug electrical wires from it but still the same, fluid looks and smells ok. Any help or ideas before giving up, thanks guys...

[maxwedge]

Make sure you have vacuum to the modulator on the trans, 2cnd also scan it and check the tps for proper operation.

[richtazz]

Have you tried shifting it manually, putting the shifter in 1, then moving it to 2, etc...? If it shifts manually, then the vacuum modulator is the problem.

[Carwhiz]

Transmission filter would be my first step if it hasn't been changed yet in the last 50K. It should be due anyways if your car has 150K.