Valve Pause System

Valve Pause System

The valve pause system is designed to reduce engine friction by closing the intake/exhaust valves of the No.2, No.3, and No.4 cylinders during deceleration. The energy corresponding to the reduced volume of engine braking power is applied to the regenerated (generation) energy of the IMA motor. As the regenerated energy increases, the system increases the assist power of the IMA motor during acceleration to improve fuel economy.




The Valve Pause System uses a synchronizing piston to lock and unlock the rocker arms from the camshaft. The synchronizing piston is driven in and out of the rocker arm by oil pressure supplied by two oil passages in the rocker shaft and controlled by a 3-way spool valve The synchronizing piston also has a light return spring to hold the rocker in the on position when there is no oil pressure. This allows the valves to operate during engine start when oil pressure is low.




Engine Oil Pressure (EOP) Sensor
The EOP sensor detects engine oil pressure for the valve pause system.




Engine Oil Temperature (EOT) Sensor
The EOT sensor detects engine oil temperature for the valve pause system.