Valve Timing Control System

Valve Timing Control Input And Output Chart:

PURPOSE

The valve timing control system is used to improve engine performance by dynamically changing intake cam timing.






ACTUATOR OPERATION

The position (amount of advancement) of the intake cams are changed by internal oil pressure acting upon a piston/servo in the timing belt pulley.

VTC Operation:

SYSTEM OPERATION
The ECU will vary the intake valve opening and closing time based on engine temperature and speed, intake air volume, throttle position and gear position.


SOLENOID VALVE
When the ECU senses the conditions necessary for increased engine performance in the low rpm band it energizes the solenoid. The solenoid extends, which in turn, closes off the bleed hole in the servo. This allows cam timing to advance, and the torque power band moves into a lower rpm range.