GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Vauxhall 🢒 2009 🢒 VXR8 🢒 Engine 🢒 Engine Controls and Fuel - 2.8L, 3.0L, 3.2L, or 3.6L 🢒 Intake Manifold Tuning Valve Diagnosis

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    •  Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

An intake manifold tuning (IMT) valve is used to change the intake manifold plenum configuration. When the IMT valve is open, the intake manifold is configured to one large plenum. When the IMT valve is closed, the intake manifold is configured to 2 smaller plenums. The IMT valve improves engine performance at low and high engine speeds.

Ignition voltage is supplied directly to the IMT solenoid. The engine control module (ECM) controls the solenoid by grounding the control circuit with a solid state device called a driver. The driver is equipped with a feedback circuit that is pulled up to a voltage. The ECM can determine if the control circuit is open, shorted to ground, or shorted to a voltage by monitoring the feedback voltage.

Diagnostic Aids
    • If the condition is intermittent, move the related harnesses and connectors, with the engine operating, while monitoring the scan tool circuit status parameters for the component. The circuit status parameters change from OK or Not Run to Fault if there is a condition with the circuit or a connection.
    • Inspect the IMT solenoid valve for witness marks that indicate that the valve was hitting the intake manifold. This condition may be temperature related.

Circuit/System Verification

Ignition ON, observe the DTC information with a scan tool. Verify that DTCs P0660, P0661, or P0662 are not set.

⇒If any of the DTCs listed are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

Circuit/System Testing
  1. Ignition OFF, remove the intake manifold tuning (IMT) valve from the intake manifold, with the electrical connector connected.
  2. Ignition ON, command the IMT solenoid ON and OFF with a scan tool. Verify that the IMT solenoid operates in both directions.
    3. ⇒If the IMT solenoid does not operate in both directions, replace the IMT solenoid.
  3. Inspect the inside of the intake manifold for the following conditions:
    4. • Carbon build-up that limits the movement of the IMT valve
    • Casting flash that limits the movement of the IMT valve
    • Foreign material that limits the movement of the IMT valve
    ⇒If a condition is found, repair as necessary.
  4. Clean or replace the upper intake manifold.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Intake Manifold Runner Control Solenoid Replacement
    •  Upper Intake Manifold Replacement