GM Service Manual Online
For 1990-2009 cars only

Inaccurate Shift Points

Checks

Cause

AT Output (Shaft) Speed Sensor Assembly (22)

    • Pinched or broken wire
    • Loose connector
    • Incorrect air gap
    • Inadequate signal
    • Damaged coil
    • Damaged rotor teeth
    • Loose connection

Throttle Position Sensor

    • Pinched or damaged wire
    • Incorrect resistance
    • Loose connector
    • PCM malfunction

AT Fluid Pressure Manual Valve Position Switch Assembly (40)

    • Loose connector
    • Loose bolts causing leakage
    • A pinched wire
    • No signal to the PCM

Axle Ratio

Ratio is incorrect or ratio has been changed from its original value.

Tire Size

Tire size is incorrect or the size has been changed from its original value.

Check PCM for current DTCs.

Only 2WD