Operation Principle: Notes

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.

Information 

• The variable force solenoid (VFS) changes its force depending on the PWM duty to control the stroke of the OCV.
• It also controls the lock, unlock, advanced, retarded, and holding functions.

1. Intake CVVT
   Fig 1: Intake CVVT Operation Chart

   Courtesy of KIA MOTORS AMERICA, INC.
2. Exhaust CVVT
   Fig 2: Exhaust CVVT Operation Chart

   Courtesy of KIA MOTORS AMERICA, INC.