GM Service Manual Online
For 1990-2009 cars only

Condition

Action

Incorrect fluid level

Correct the fluid level. Refer to Transmission Fluid Check .

Plugged or faulty suction filter

Clean or replace the oil suction filter element. Refer to Oil Pan Replacement .

Main pressure regulator valve sticking

Overhaul the control module assembly.

Leaking solenoids in control valve body assembly

Replace the solenoids. Refer to Control Valve Solenoid Replacement .

Main pressure regulator valve spring weak, broken, or missing

Inspect the spring and replace, if necessary.

Control module body leakage - separator plate not flat, loose control valve body bolts

Replace or rebuild the control module assembly. Care should be taken when removing and labeling shift springs.

Faulty or incorrect fluid pressure gage

Repair or replace the gage.

Oil pump worn or damaged

Replace or rebuild the oil pump.

Leak in suction circuit

Inspect the suction circuit for leaking seal, gasket, or mating surface.