Intake Manifold Runner Control System Diagnosis. Cadillac CTS 2004

For 1990-2009 cars only

Makes 🢒 Cadillac 🢒 2004 🢒 CTS 🢒 Engine 🢒 Engine Controls - 3.6L (LY7) 🢒 Intake Manifold Runner Control System Diagnosis

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.

Diagnostic Aids

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

Test Description

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

This diagnostic table will only diagnose the mechanical portion of the IMRC solenoid. If there is a DTC set for the IMRC solenoid, refer to the appropriate DTC table.

Step

Action

Values

Yes

Did you perform the Diagnostic System Check-Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

Turn ON the ignition, with the engine OFF.
Observe the DTC information with a scan tool.

Is DTC P2008, P2009, or P2010 set?

Go to Diagnostic Trouble Code (DTC) List

Go to Step 3

Remove the intake manifold runner control (IMRC) solenoid from the intake manifold, but leave the electrical connector connected. Refer to Intake Manifold Runner Control Solenoid Replacement .

Important: The IMRC Command parameter may not change from OFF to ON or ON to OFF when using the IMRC output control.

Command the IMRC solenoid ON and OFF with a scan tool.
Observe the valve of the IMRC solenoid while you command the IMRC solenoid ON and OFF.

Does the valve of the IMRC solenoid move in both directions?

Go to Step 4

Go to Step 5

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

•	For carbon build-up that limits the movement of the IMRC valve

•	For casting flash that limits the movement of the IMRC valve

•	For foreign material that limits the movement of the IMRC valve

Clean or replace the upper intake manifold. Refer to Upper Intake Manifold Replacement in Engine Mechanical - 3.6L (LY7).

Did you find and correct the condition?

Go to Step 6

Go to Diagnostic Aids

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

Did you complete the replacement?

Go to Step 6

Connect all disconnected components.
Clear the DTCs with a scan tool.
Start the engine.
Operate the system in order to verify the repair.

Did you correct the condition?

Go to Step 7

Go to Step 2

Observe the capture info with a scan tool.

Are there any DTCs that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List

System OK