GM Service Manual Online
For 1990-2009 cars only

Harsh Shifts

Checks

Causes

Throttle Position Sensor

Open or shorted circuit

Vehicle Speed Sensor

Open or shorted circuit

Automatic Transmission Fluid Pressure (TFP)

    • Contamination
    • Damaged seals

Trans Fluid Temperature Sensor

Open or shorted circuit

Engine Coolant Temperature Sensor

Open or shorted circuit

Pressure Control Solenoid

    • Damage to pins
    • Contamination