Kia Rio: Description

Continuous Variable Valve Timing (CVVT) system advances or retards the valve timing of the intake and exhaust valve in accordance with the ECM control signal which is calculated by the engine speed and load.

By controlling CVVT, the valve over-lap or under-lap occurs, which makes better fuel economy and reduces exhaust gases (NOx, HC) and improves engine performance through reduction of pumping loss, internal EGR effect, improvement of combustion stability, improvement of volumetric efficiency, and increase of expansion work.

This system consist of

The engine oil getting out of the CVVT oil control valve varies the cam phase in the direction (Intake Advance/Exhaust Retard) or opposite direction (Intake Retard/Exhaust Advance) of the engine rotation by rotating the rotor connected with the camshaft inside the cam phaser.

Components

1. Exhaust camshaft 2. Intake camshaft 3. Exhaust CVVT 4. Intake CVVT 5. Camshaft bearing cap 6. Camshaft front bearing cap 7. O-ring 8. Oil control valve (OCV) ada ...

Operation Principle

The CVVT has the mechanism rotating the rotor vane with hydraulic force generated by the engine oil supplied to the advance or retard chamber in accordance with the CVVT oil control valve con ...

See also:

A/C Pressure Transducer Description
The A/C Pressure Transducer (APT) convert the pressure value of high pressure line into voltage value after measure it. By converted voltage value, engine ECU controls cooling fan by operatin ...

Removal
   When replacing the ECM, the vehicle equipped with immobilizer must be performed the procedure as below. ...

Fuel Tank Removal
1. Release the residual pressure in fuel line (Refer to the Fuel Delivery System - Repair Procedures - "Release Residual Pressure in Fuel Line"). ...