Circuit Description

WARNING: This page is about a different car, the 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

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 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 ignition voltage circuit and the IMRC control circuit are routed to the IMRC solenoid thru an IMRC driver module. The IMRC driver module is an amplifier that is used to strengthen the IMRC solenoids ability to remain in the commanded position during high load and current demands.