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For 1990-2009 cars only

Circuit 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. If the ECM detects the control circuit voltage is within a predetermined range when the circuit is commanded OFF, this DTC sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

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

Conditions for Running the DTC

    • The engine speed is more than 80 RPM.
    • The ignition 1 voltage is between 10-18 volts.
    • The ECM has commanded the IMRC solenoid ON and OFF at least once during the ignition cycle.
    • DTC P2008 runs continuously once the above conditions are met.

Conditions for Setting the DTC

    • The ECM detects the control circuit voltage for the IMRC solenoid is between 2.6-4.6 volts when the driver is commanded OFF.
    • The condition exists for less than 1 second.

Action Taken When the DTC Sets

    • The control module stores the DTC information into memory when the diagnostic runs and fails.
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
    • The driver information center, if equipped, may display a message.

Conditions for Clearing the DTC

    • A current DTC Last Test Failed clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
    • Clear the DTC with a scan tool.

Diagnostic Aids

    • Use the J 35616-A/BT-8637 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector.
    • The lower connector of the ECM is connector C1 and the upper connector of the ECM is connector C2. Refer to Engine Controls Component Views .
    • If the condition is intermittent, move the related harnesses and connectors, with the engine operating, while monitoring the circuit status for the component with a scan tool. The circuit status parameter changes from OK or Indeterminate to Fault if there is a condition with the circuit or a connection. The ODM information is in the output driver module (ODM) data list.
    • For an intermittent condition, refer to Intermittent Conditions .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Listen for an audible click when the IMRC solenoid operates. Command both the ON and OFF states. Repeat the commands as necessary.

  2. This step tests the ignition 1 voltage circuit to the IMRC solenoid.

  3. This step tests the control modules ability to supply a ground to the IMRC solenoid.

  4. This step tests the feedback voltage from the ECM. If a voltage is not available, this indicates an internal ECM condition.

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

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Start the engine.
  2. Observe the DTC information with a scan tool.

Does the DTC fail this ignition?

--

Go to Step 4

Go to Step 3

3

  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 4

Go to Diagnostic Aids

4

  1. Turn OFF the ignition.
  2. Disconnect the intake manifold runner control (IMRC) solenoid.
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the ignition 1 voltage circuit of the IMRC solenoid with a test lamp that is connected to the engine control module (ECM) housing.

Does the test lamp illuminate?

--

Go to Step 5

Go to Step 10

5

  1. Connect a test lamp between the control circuit of the IMRC solenoid and the ignition 1 voltage circuit of the IMRC solenoid.
  2. Command the IMRC solenoid ON and OFF with a scan tool.

Does the test lamp turn ON and OFF?

--

Go to Step 6

Go to Step 7

6

Measure the voltage from the control circuit of the IMRC solenoid to the ECM housing with a DMM.

Is the voltage within the specified range?

2.6-4.6 V

Go to Step 8

Go to Step 12

7

Test the control circuit of the IMRC solenoid for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 13

Go to Step 9

8

Test for an intermittent and for a poor connection at the IMRC solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 13

Go to Step 11

9

Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 13

Go to Step 12

10

  1. Repair the ignition 1 voltage circuit of the IMRC solenoid for an open or for an intermittent short to ground.
  2. Replace the fuse as necessary.

Did you complete the repair?

--

Go to Step 13

--

11

Replace the IMRC solenoid. Refer to Intake Manifold Runner Control Solenoid Replacement .

Did you complete the replacement?

--

Go to Step 13

--

12

Replace the ECM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 13

--

13

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 14

14

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK