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2007 > 2.7L V6 GASOLINE >
DESCRIPTION
The CVVT (Continuously Variable Valve Timing) which is installed on the exhaust camshaft controls intake valve open
and close timing in order to improve engine performance.
The intake valve timing is optimized by CVVT system depending on engine rpm.
This CVVT system improves fuel efficiency and reduces NOx emissions at all levels of engine speed, vehicle speed,
and engine load by EGR effect because of valve over - lap optimization.
The CVVT changes the phase of the intake camshaft via oil pressure.
It changes the intake valve timing continuously.
OPERATION
The CVVT system makes continuous intake valve timing changes based on operating conditions.
Intake valve timing is optimized to allow the engine to produce maximum power.
Cam angle is advanced to obtain the EGR effect and reduce pumping loss. The intake valve is closed quickly to
reduce the entry of the air/fuel mixture into the intake port and improve the changing effect.
Reduces the cam advance at idle, stabilizes combustion, and reduces engine speed.
If a malfunction occurs, the CVVT system control is disabled and the valve timing is fixed at the fully retarded position.
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1.The above figure shows the relative operation structures of the housing vane to the rotor vane.
2. If the CVVT is held a certain control angle, to hold this state, oil is replenished as much as oil leaks from the oil
pump.
The OCV (Oil - flow Control Valve) spool location at this time is as follows.
Oil pump → Advance oil chamber (Little by little open the inflow side to the advance oil chamber) → Almost close the
drain side
Be sure there might be a difference in the position according to the engine running state (rpm, oil temperature, and oil
pressure).
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2007 > 2.7L V6 GASOLINE >
SPECIAL SERVICE TOOLS
Tool
(Number and name) Illustration
Application
09353 - 24100
Fuel Pressure Gauge
Measuring the fuel line pressure
09353 - 38000
Fuel Pressure Gauge
Adapter
Connection between the delivery pipe and
fuel feed line
09353 - 24000
Fuel Pressure Gauge
Connector
Connection between Fuel Pressure Gauge
(09353- 24100) and Fuel Pressure Gauge
Adapter (09353- 38000)
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2007 > 2.7L V6 GASOLINE >
BASIC TROUBLESHOOTING
BASIC TROUBLESHOOTING GUIDE
CUSTOMER PROBLEM ANALYSIS SHEET
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BASIC INSPECTION PROCEDURE
The measured resistance at high temperature after vehicle running may be high or low. So all resistance must be
measured at ambient temperature (20°C, 68°F), unless stated otherwise.
The measured resistance in except for ambient temperature (20°C, 68°F) is reference value.
Sometimes the most difficult case in troubleshooting is when a problem symptom occurs but does not occur again
during testing. An example would be if a problem appears only when the vehicle is cold but has not appeared when
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during testing. An example would be if a problem appears only when the vehicle is cold but has not appeared when
warm. In this case, the technician should thoroughly make out a "CUSTOMER PROBLEM ANALYSIS SHEET" and
recreate (simulate) the environment and condition which occurred when the vehicle was having the issue.1. Clear Diagnostic Trouble Code (DTC).
2. Inspect connector connection, and check terminal for poor connections, loose wires, bent, broken or corroded pins,
and then verify that the connectors are always securely fastened.
3.Slightly shake the connector and wiring harness vertically and horizontally.
4. Repair or replace the component that has a problem.
5. Verify that the problem has disappeared with the road test.
● SIMULATING VIBRATION
a. Sensors and Actuators
: Slightly vibrate sensors, actuators or relays with finger.
Strong vibration may break sensors, actuators or relays
b. Connectors and Harness
: Lightly shake the connector and wiring harness vertically and then horizontally.
● SIMULATING HEAT
a. Heat components suspected of causing the malfunction with a hair dryer or other heat source.
a.DO NOT heat components to the point where they may be damaged.
b. DO NOT heat the ECM directly.
● SIMULATING WATER SPRINKLING
a. Sprinkle water onto vehicle to simulate a rainy day or a high humidity condition.
DO NOT sprinkle water directly into the engine compartment or electronic components.
● SIMULATING ELECTRICAL LOAD
a. Turn on all electrical systems to simulate excessive electrical loads (Radios, fans, lights, rear window defogger,
etc.).
CONNECTOR INSPECTION PROCEDURE