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 cuts 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 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.
Inspection
1.
Connect the GDS on the Data Link Connector (DLC).
2.
Measure the output voltage of the RPS at idle and various engine speed.
ConditionOutput Voltage (V)Idle Approx. 1.21, ...
Your vehicle's fuel economy depends
mainly on your style of driving, where
you drive and when you drive.
Each of these factors affects how
many miles (kilometers) you can get
from a gallon (liter) of fuel.To operate
your vehicle as economically as possible,
use the following driving sug ...
Removal and Installation
1.
Remove the drive belt.
(Refer to Timing System - "Drive Belt")
2.
Remove the drive belt idler (A).
Tightening torque :
53.9 ~ 57.9 N.m (5.5 ~ 5.9 kgf.m, 39.8 ~ 42.7 lb-ft)
3.
Installation is reverse order of removal
Inspection
Check the idler for e ...