Hyundai Santa Fe: Exhaust Emission Control System / CVVT (Continuously Variable Valve Timing) System. Description and operation
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
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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,
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the CVVT Oil Temperature Sensor (OTS) which measures the engine oil
temperature,
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and the Cam Phaser which varies the cam phase by using the hydraulic
force of the engine oil.
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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.
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.
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The variable force solenoid (VFS) changes its force depending
on the PWM duty to control the stroke of the OCV.
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It also controls the lock, unlock, advanced, retarded, and holding
functions.
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(1) Low Speed / Low Load
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(2) Part Load
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(3) Low Speed / High Load
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(4) High Speed / High Load
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Driving Condition
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Exhaust Valve
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Intake Valve
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Valve Timing
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Effect
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Valve Timing
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Effect
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(1) Low Speed
/Low Load
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Completely Advance
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* Valve Under-lap
* Improvement of combustion stability
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Completely Retard
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* Valve Under-lap
* Improvement of combustion stability
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(2) Part Load
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Retard
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* Increase of expansion work
* Reduction of pumping loss
* Reduction of HC
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Retard
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* Reduction of pumping loss
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(3) Low Speed
/High Load
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Retard
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* Increase of expansion work
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Advance
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* Prevention of intake back flow (Improvement of volumetric efficiency)
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(4) High Speed
/High Load
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Advance
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* Reduction of pumping loss
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Retard
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* Improvement of volumetric efficiency
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Removal
[Catalytic Converter (WCC)]
1.
Remove the exhaust manifold.
(Refer to Engine Mechanical System - "Exhaust Manifold")
[Catalytic Converter (UCC)]
1...
Other information:
Components
1. Front door
window glass
2. Front door window glass run assembly
3. Front door outside handle
4. Front door lock assembly
5. Front door outside handle pad
6. Front door
checker assembly
7...
First secure the child restraint with the LATCH lower anchors or the seat belt.
If the child restraint manufacturer recommends that the top tether strap be attached,
attach and tighten the top tether strap to the top tether strap anchor.
Child restraint hook holders are located on the rear of the seatbacks...
Categories
Electric Power Steering (EPS) warning light
This warning light illuminates:
When you set the ignition switch or the Engine Start/Stop button to
the ON position.
- The electric power steering warning light illuminates for about 3 seconds
and then goes off.
Whenever there is a malfunction with the electric power steering.
If this occurs, have the vehicle inspected by an authorized HYUNDAI dealer.
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