Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. 4. This will check the wastegate solenoid and filter. If the filter is plugged, the filter will not allow the solenoid to vent, and this will cause an overboost condition.
2. 5. This step checks the turbocharger wastegate actuator for vacuum leaks. The actuator must hold vacuum.
3. 6. This step will check for vacuum leaks at the lines.
4. 9. This step will check for a skewed boost pressure sensor.

Fig 1: DTC P0236 (Steps 1-9)

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC P0236 (Steps 10-17)

Courtesy of GENERAL MOTORS CORP.