GM Service Manual Online
For 1990-2009 cars only

Check

Causes

DEFINITION: A large engine RPM increase and forward vehicle speed decrease do not immediately occur when the transmission is shifted from Overdrive or fourth gear in Drive or manual third range to first.

Low and Reverse Clutch

    • Damaged or cut piston
    • Damaged or worn clutch plates

Control Valve Body Accumulator Assembly

    • 3-4 shift control valve stuck
    • 3-4 shift valve stuck - 1st, 2nd or 3rd gear
    • Low pressure control valve - 1st, 2nd or 3rd gears
    • 4-5 SS valve stuck off - 1st, 2nd , or 3rd gears
    • 4-5 shift valve stuck applied - 1st, 2nd, 3rd gears
    • 3-4 shift valve and/or 3-4 control shift valve stuck released
    • Low pressure control valve stuck released
    • 4-5 shift valve and/or 4-5 control shift valve stuck released
    • 1-2 shift valve stuck released