Engine Mount Control Unit: Description and Operation

NOTE: Unlike previous liquid engine mounts, this engine mount control system reduces vibration at idle range without affecting vibration damping above idle.

DESCRIPTION
The system is comprised of the Powertrain Control Module (PCM), the solenoid valve and the rear mount with built-in diaphragm actuator.





OPERATION
The PCM receives the engine rpm signals and sends a signal to the solenoid valve to open only at idle. When the solenoid valve opens, intake manifold vacuum is applied to the diaphragm actuator, and the rotor valve located in the rear mount rotates 80 degrees. The mount has Chamber A on its upper part and Chamber B on the lower part. The rotor valve located between these two chambers controls the quantity of liquid that flows between them.





At idle, the rotor valve opens, and liquid flows through passages 1 and 2. Dampening decreases, and vibration at idle is reduced.








Above idle, passage 1 is closed, and liquid flows only through passage 2. Dampening increases, and vibration above idle is reduced.