CVVT Oil Control Valve (OCV)

The Continuously Variable Valve Timing (CVVT) system advances or retards the intake and exhaust valve timing in accordance with the ECM control signal, which is calculated based on engine speed and load. Under CVVT control, valve overlap or underlap is adjusted, which results in better fuel economy, reduced exhaust emissions (NOx, HC), and improved engine performance by reducing pumping losses, improving internal exhaust gas recirculation effect, improving combustion stability, increasing volumetric efficiency, and increasing expansion work. This system consists of: - CVVT Oil Control Valve (OCV), which supplies engine oil to the cam phaser or shuts off engine oil from the cam phaser in accordance with the ECM PWM (Pulse Width Modulation) control signal, - CVVT Oil Temperature Sensor (OTS), which measures the engine oil temperature, - and Cam Phaser, which changes the camshaft phase by means of engine oil hydraulic pressure. Engine oil flowing from the CVVT oil control valve changes the camshaft phase in the intake advance/exhaust retard direction or in the opposite direction (intake retard/exhaust advance) relative to engine rotation, as the rotor connected to the camshaft rotates inside the cam phaser.