GM Service Manual Online
For 1990-2009 cars only

Check

Causes

DEFINITION: A large engine RPM increase is noted, with no vehicle forward speed increase, during the following conditions:

    • The engine is running.
    • The transmission is in Drive range.
    • The vehicle is stopped or moving slowly.
    • The vehicle brakes are not applied.
    • The throttle is opened 25 percent or greater.

Forward Clutch Assembly

    • Damaged or worn clutch plates
    • Damaged or cut piston
    • Damaged or stuck ball check valve

Forward Clutch Sprag

    • Damaged sprag
    • Worn or pitted inner race

Fluid Pump

    • Damaged vanes
    • Missing slide spring
    • Fluid pump screen assembly plugged or damaged
    • Fluid pump rotor guide omitted or misassembled
    • Fluid pump rotor cracked or broken
    • Porosity in fluid pump
    • Fluid pump surfaces not flat
    • Excessive fluid pump rotor clearance

Low Clutch Sprag

    • Damaged sprag
    • Worn or pitted inner race

Input and Reaction Carrier

Damaged or worn gears