Perform the Diagnostic System Check - Vehicle.

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

Ignition voltage is supplied directly to the IMRC 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.

Inspect the IMRC solenoid valve for witness marks that indicate that the valve was hitting the intake manifold. This condition may be temperature related.

Ignition ON, observe the DTC information with a scan tool. Verify that DTCs P2008, P2009, or P2010 are not set.

1. Ignition OFF, remove the intake manifold runner control (IMRC) solenoid from the intake manifold, with the electrical connector connected.
2. Ignition ON, command the IMRC solenoid ON and OFF with a scan tool. Verify that the IMRC solenoid operates in both directions.

⇒	If the IMRC solenoid does not operate in both directions, replace the IMRC solenoid.

3. Inspect the inside of the intake manifold for the following conditions:

•	Carbon build-up that limits the movement of the IMRC valve

•	Casting flash that limits the movement of the IMRC valve

•	Foreign material that limits the movement of the IMRC valve

⇒	If a condition is found, repair as necessary.

4. Clean or replace the upper intake manifold.

Perform the Diagnostic Repair Verification.