KIA Niro: CVVT & Camshaft Description and operation
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, 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 increased expansion work.
This system consists of
- the CVVT Oil Control Valve (OCV) which supplies the engine oil to the
cam phaser or runs out the engine oil from the cam phaser in accordance with
the ECM
PWM (Pulse With Modulation) control signal, - the CVVT Oil Temperature Sensor (OTS) which measures the engine oil temperature,
- and the Cam Phaser which varies the cam phase by using the hydraulic force of the engine oil.
The engine oil released from 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.
Operation Principle
The CVVT has the mechanism of 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.
- Intake CVVT
- Exhaust CVVT
CVVT System Mode
- Low Speed / Low Load
- Partial Load
- Low Speed / High Load
- High Speed / High Load
READ NEXT:
CVVT & Camshaft Repair procedures
Removal Warning Use fender covers to avoid damaging painted surfaces. To avoid damaging the cylinder head, wait until the engine coolant temperature drops below normal temperature (20ºC (68ºF)) before removing it. When handling a metaCylinder Head Repair procedures
Removal Engine removal is not required for this procedure. Warning Be sure to read and follow the "General Safety Information and Caution" before doing any work related with the high voltage system. Failure to follow the safety instructionCylinder Head
Inspect for flatness. Using a precision straight edge and feeler gauge, measure the contacting surface of the cylinder block and check the manifolds for warpage. If the flatness is greater than maximum, replace the cylinder head. FlaSEE MORE:
Thermostat Repair procedures
Removal and Installation Warning Disassembly of the thermostat may have an adverse effect, causing deteriorated cooling efficiency. Do not remove the thermostat, even if the engine tends to overheat. Remove the engine room under cover. (RPower limited
A: Power limited In the following cases, this warning message is displayed when the vehicle's power is limited for safety. When the power is limited for the safety of the high-powered parts of an electric vehicle. The power is limiCategories
- Home
- KIA Niro EV, Hybrid - Second generation - (SG2) (2021-2024) - Owner's manual
- Kia Niro - First generation - (DE) (2017-2022) - Service and Repair Manual
- Contact Us