Operation CHARM: Car repair manuals for everyone.

Variable Valve Timing Actuator: Description and Operation






Camshaft Adjustment Valves

Electric solenoid valves are used on each adjustable camshaft to control the flow of engine oil to the adjuster, and are operated by a Pulse Width Modulated (PWM) signal from the Engine Control Module (ECM). Each camshaft also has its own camshaft position sensor to verify camshaft position.