Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.

Verify the conditions listed below do not exist:
- Induction/charge air cooler system leaks. Refer to Charge Air Cooler Diagnosis (Induction System Air Leak Test) , Charge Air Cooler Diagnosis (Induction System Smoke Test) and Charge Air Cooler Diagnosis - Induction System Smoke Test.
- Collapsed or restricted intake duct system.
- Air flow restrictions, including the air filter.
- Leaks at the positive crankcase ventilation (PCV) heater to air cleaner outlet duct interface.
- Splits, kinks or improper connections at the vacuum hoses.
- Vacuum leaks.
- Missing, restricted or leaking exhaust components. Refer to Symptoms - Engine Exhaust .
- Loose or incorrect installation of any components.
- Aftermarket components.
- Incorrect fuel content.
- Damaged turbocharger vane control solenoid.
- Damaged or restricted turbocharger vane control actuator.
- If a condition is found
  Repair or replace the affected component as necessary.
- If no condition is found
Disconnect the vacuum supply hose from the Q41 Turbocharger Vane Position Control Solenoid Valve and connect the GE 23738-A to the hose.
Engine running, verify the vacuum is greater than 50 kPa (14.8 in. Hg.).
- If 50 kPa (14.8 in. Hg.) or less
1. Verify the conditions listed below do not exist:
  - Vacuum tank filter restriction or damage.
  - Vacuum tank leak or damage.
    - If a condition is found repair or replace the component as necessary.
    - If no condition is found, replace the vacuum pump.
- If greater than 50 kPa (14.8 in. Hg.)
Ignition OFF, reconnect the vacuum supply hose to the Q41 Turbocharger Vane Position Control Solenoid Valve.
Engine running, verify the Turbocharger Vane Position Sensor is greater than 95% when commanding the Turbocharger Vane Position Solenoid Valve ON with a scan tool.
- If 95% or less
  Replace the Q41 Turbocharger Vane Position Control Solenoid Valve.
- If greater than 95%
Verify the Turbocharger Vane Position Sensor is less than 5% when commanding the Turbocharger Vane Position Solenoid Valve OFF with a scan tool.
- If 5% or greater
  Replace the Q41 Turbocharger Vane Position Control Solenoid Valve.
- If less than 5%
Inspect the turbocharger oil supply lines for a leak or restriction.
- If any leaks or restrictions are found
  Repair or replace the oil supply lines as necessary.
- If no leaks or restrictions are found
Verify the conditions listed below do not exist:
- Damaged turbocharger.
- Debris in the turbocharger.
- Sticking or obstructed turbocharger vanes.
  Refer to Turbocharger Cleaning and Inspection .
- If a condition exists
  Repair the condition or replace the component as necessary.
- If none of the conditions exist
Replace the turbocharger.