Hyundai Santa Fe: Cylinder Head Assembly / CVVT & Camshaft. Description and operation

Hyundai Santa Fe (TM) 2019-2024 Service Manual / Engine Mechanical System / Cylinder Head Assembly / 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 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 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,

–	and the Cam Phaser which varies the cam phase by using the hydraulic force of the engine oil.

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.

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 control.

•	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.

[CVVT System Mode]

(1) Low Speed / Low Load	(2) Part Load

(3) Low Speed / High Load	(4) High Speed / High Load

Driving Condition	Exhaust Valve		Intake Valve
Driving Condition	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

Cylinder Head Cover. Repair procedures

Removal 1. Disconnect the battery negative terminal. 2. Remove the engine cover. • Remove the engine cover on room temperature...

CVVT & Camshaft. Repair procedures

Removal • Be careful not to damage the parts located under the vehicle (floor under cover, fuel filter, fuel tank and canister) when raising the vehicle using the lift...

Other information:

Hyundai Santa Fe (TM) 2019-2024 Service Manual: Special service tools

Special Service Tools Engine Tools (Number and name) Illustration Use Diesel 2.2 TCI Oil seal installer 09473-D3600 Used for installing the transfer case oil seal (Driveshaft side) (Used with the handle) Handle 09231-H1100 Used for installing the transfer case oil seal (Used with the oil seal installer) Gasoline 2...

Hyundai Santa Fe (TM) 2019-2024 Owner's Manual: Forward Collision-Avoidance Assist Settings

Forward Safety With the engine on, select ‘Driver Assistance - Forward Safety' from the Settings menu to set whether or not to use each function. - Id 'Active Assist' is selected, Forward Collision-Avoidance Assist - will warn the driver with a warning message and an audible warning depending on the collision risk levels...