Intake Manifold Runner Control (IMRC) System
WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2019 Lincoln Navigator, 2019 Lincoln Nautilus, 2019 Lincoln MKZ, 2019 Lincoln MKT, and 2019 Lincoln MKC. However, it is still accessible from the selected car via links, so may be relevant.
WARNING:
SUBSTANTIAL OPENING AND CLOSING TORQUE IS APPLIED BY THIS SYSTEM. TO PREVENT INJURY, BE CAREFUL TO KEEP FINGERS AWAY FROM LEVER MECHANISMS WHEN ACTUATED. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.
The IMRC system consists of a manifold mounted vacuum actuator and a PCM controlled electric solenoid. For additional information on IMRC vacuum actuated components, refer to ENGINE CONTROL COMPONENTS . The linkage from the actuator attaches to the manifold plate lever. The IMRC vacuum actuator and manifold has a single intake air passage for each cylinder. The passage has a valve plate that blocks a large percentage of the opening when actuated, leaving the top of the passage open to generate turbulence. The housing uses a return spring to hold the valve plates open. The IMRC sensors provide feedback to the PCM indicating the valve plate position.
- The PCM monitors the TP sensor, cylinder head temperature (CHT) sensor, and CKP sensor signals to determine activation of the IMRC system. There must be a positive change in voltage from the TP sensor along with the increase in RPM at the correct engine temperature to open the IMRC valve plates.
- The PCM uses the information from the input signals to control the IMRC solenoid based upon changes in the throttle position, the engine temperature, and the RPM.
- The PCM energizes the IMRC solenoid with the ignition ON and the engine running. Vacuum is then applied to the actuator to pull the valve plates closed.