GM Service Manual Online
For 1990-2009 cars only

Harsh Shifts

Checks

Causes

Throttle Position Sensor

Open or shorted circuit

Vehicle Speed Sensor (36)

Open or shorted circuit

Automatic Transmission Fluid Pressure (TFP) (69)

    â€¢ Contamination
    â€¢ Damaged seals

Trans Fluid Temperature Sensor (Part of 69)

Open or shorted circuit

Engine Coolant Temperature Sensor

Open or shorted circuit

Pressure Control Solenoid (377)

    â€¢ Damage to electrical terminals
    â€¢ Contamination