Intake Manifold Tuning Valve Diagnosis
Diagnostic Instructions
Circuit/System Description
An intake manifold tuning valve is used to change the intake manifold plenum configuration. When the intake manifold tuning valve is open, the intake manifold is configured to one large plenum. When the intake manifold tuning valve is closed, the intake manifold is configured to 2 smaller plenums. The intake manifold tuning valve improves engine performance at low and high engine speeds depending on the engine load. Ignition voltage is supplied directly to the intake manifold tuning valve solenoid. The engine control module (ECM) controls the solenoid by grounding the control circuit. The intake manifold tuning valve system contains the following components:
• | The intake manifold tuning valve solenoid |
• | The intake manifold tuning valve vacuum reservoir |
• | The intake manifold tuning valve vacuum actuator |
• | The intake manifold tuning valve |
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Air Inlet System Description
Electrical Information Reference
Special Tools
For equivalent regional tools, refer to Special Tools .
Circuit/System Verification
- Engine running, verify that DTC P2008 00 is not set.
- If the DTC is set, refer to DTC P2008 .
- Engine running, command the Q22 Intake Manifold Tuning Solenoid Valve ON with a scan tool. The Q22 Intake Manifold Tuning Solenoid Valve vacuum actuator should move to the closed position.
Circuit/System Testing
- Ignition OFF, disconnect the vacuum hose at the vacuum intake manifold tuning solenoid valve vacuum actuator.
- Install the EN 23738-A Mityvac or EN 35555 Metal Mityvac to the port of the vacuum actuator. Apply 51 kPa (7.3 PSI) of vacuum to the vacuum actuator. Verify the vacuum actuator moves, and that the vacuum remains steady.
⇒ | If the vacuum actuator does not move, replace the intake manifold tuning solenoid valve vacuum actuator. |
⇒ | If the vacuum decreases, replace the intake manifold tuning solenoid valve vacuum actuator. |
- Disconnect the harness connector at the Q22 Intake Manifold Tuning Solenoid Valve.
- Ignition ON, verify a test lamp illuminates between the ignition voltage circuit terminal 1 and ground.
⇒ | If the test lamp does not illuminate, repair the ignition voltage circuit for a short to ground or an open/high resistance. Replace the fuse F47, if necessary. |
- Ignition OFF, connect a test lamp between the control circuit terminal 2 and the ignition voltage circuit terminal 1.
- Engine running, command the Q22 Intake Manifold Tuning Solenoid Valve ON and OFF with a scan tool. The test lamp should turn ON when the solenoid is commanded OFF, and OFF when the solenoid is commanded ON.
⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
- Connect the vacuum hose to the vacuum actuator.
- Connect the harness connector at the Q22 Intake Manifold Tuning Solenoid Valve.
Note: The vacuum displayed on the EN 23738-A Mityvac or EN 35555 Metal Mityvac should decrease after engine start, and then stabilise.
- Disconnect the vacuum supply hose from the intake manifold.
- Connect EN 23738-A Mityvac or EN 35555 Metal Mityvac to the vacuum supply hose. Apply 51 kPa (7.3 PSI) of vacuum to the vacuum supply hose. Engine running, verify the vacuum decreases.
⇒ | If the vacuum does not decrease, repair the restriction, or replace the Q22 Intake Manifold Tuning Solenoid Valve. |
- Engine running, monitor the vacuum display. Verify the vacuum stabilises and remains steady.
⇒ | If the vacuum decreases, repair the vacuum leak. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for ECM replacement, setup, and programming
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