GM Service Manual Online
For 1990-2009 cars only

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.

DTC Descriptors

DTC P2008: Intake Manifold Runner Control (IMRC) Solenoid Control Circuit

DTC P2009: Intake Manifold Runner Control (IMRC) Solenoid Control Circuit Low Voltage

DTC P2010: Intake Manifold Runner Control (IMRC) Solenoid Control Circuit High Voltage

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Ignition Voltage

P2009*

P2008

--

P2076

IMT/IMRC Control Circuit

P2009, P2076

P2008

P2010

P2076

IMT/IMRC Signal Circuit

P2077

P2076, P2077, P2078

P2076, P2077, P2078

P2076

IMT/IMRC Ground

--

P2076, P2077, P2078

--

P2076

*Opens the fuse that supplies voltage to the IMT/IMRC solenoid.

Circuit/System Description

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 two 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.

The IMRC valve also contains a position sensor which is used to detect the actual position of the IMRC valve in relation to its commanded position. The ECM supplies the IMRC position sensor with a 5-volt signal circuit and the position sensor uses a common ground circuit. The position sensor enables the ECM to detect a physically broken or stuck IMRC valve.

Conditions for Running the DTC

    • The ignition is ON or the engine is operating.
    • The IMRC solenoid has been commanded ON and OFF at least once during the ignition cycle.
    •  The DTCs run continuously once the above condition is met.

Conditions for Setting the DTC

The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than a cumulative of 50 seconds.

Action Taken When the DTC Sets

DTCs P2008, P2009, and P2010 are Type C DTCs.

Conditions for Clearing the DTC

DTCs P2008, P2009, and P2010 are Type C DTCs.

Diagnostic Aids

If the condition is intermittent, move the related harnesses and connectors, with the engine idling, while monitoring the scan tool circuit test status parameters for the component. A circuit test status parameter will change from OK or Not Run to Fault if there is a condition with the circuit or a connection.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Air Intake System Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Ignition ON, command the IMRC solenoid ON and OFF with a scan tool, while Observing the scan tool circuit test status parameters for the IMRC solenoid. The parameters should display OK or Not Run in each commanded state.
  2. Ignition ON, command the IMRC solenoid ON and OFF with a scan tool. You should hear and feel an audible click.
  3. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the IMRC solenoid.
  2. Verify a test lamp illuminates between the ground circuit terminal D and B+.
  3. If the test lamp does not illuminate, repair the open/high resistance in the ground circuit.
  4. Ignition ON, load test for B+ between the ignition voltage circuit terminal E and ground.
  5. If less than the specified range, repair the short to ground open/high resistance on the ignition 1 voltage circuit. Replace the fuse, if necessary.
  6. Ignition OFF, connect a test lamp between the control circuit terminal C and the ignition voltage circuit terminal E.
  7. Ignition ON, command the IMRC solenoid ON with a scan tool. The test lamp should turn ON and OFF.
  8. If the test lamp remains ON all the time, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM.
    If the test lamp remains OFF all the time, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
  9. Test for 2-3 volts between the control circuit terminal C and ground
  10. If the voltage is not within the specified range, replace the ECM.
  11. If all circuits test normal, replace the IMRC solenoid.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Intake Manifold Runner Control Solenoid Replacement
    •  Control Module References for engine control module replacement, setup, and programming