Operation Principle
WARNING: This page is about a different car, the 2021 Kia Soul. However, it is still accessible from the selected car via links, so may be relevant.
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 control.
| Driving Condition | Exhaust Valve | Intake Valve | ||
|---|---|---|---|---|
| Valve Timing | Effect | Valve Timing | Effect | |
| (1) Low Speed/Low Load | Completely Advance |
* Valve Under-lap * Improvement of combustion stability |
Completely Retard |
* Valve Under-lap * Improvement of combustion stability |
| (2) Part Load | Retard | * Increase of expansion work * Reduction of pumping loss * Reduction of HC |
Retard | * Reduction of pumping loss |
| (3) Low Speed/High Load | Retard | * Increase of expansion work | Advance | * Prevention of intake back flow (Improvement of volumetric efficiency) |
| (4) High Speed/High Load | Advance | * Reduction of pumping loss | Retard | * Improvement of volumetric efficiency |