ENGINE - 1NZ-FE ENGINE
247EG23
Camshaft Timing Oil Control Valve
Throttle Position
Sensor
Camshaft Position
Sensor
Engine Coolant
Temperature
Sensor
ECM
Mass Air
Flow Meter
Crankshaft Position Sensor
221EG16
Crankshaft Position Sensor
Mass Air Flow Meter
Engine Coolant Temp. Sensor
Camshaft Position Sensor
Vehicle Speed Sensor
Throttle Position Sensor
Target Valve Timing
Duty-cycle
Control
Feedback
Correction
Actual Valve Timing
Camshaft
Timing
Oil
control
Valve
EG-41
7. VVT-i (Variable Valve Timing-intelligent) System
General
The VVT-i system is designed to control the intake camshaft within a range of 40
(of Crankshaft Angle)
to provide valve timing that is optimally suited to the engine condition. This realizes proper torque in
all the speed ranges as well as realizing excellent fuel economy, and reducing exhaust emissions.
Using the engine speed signal, vehicle speed signal, and the signals from mass air flow meter, throttle
position sensor and water temperature sensor, the engine ECU can calculate optimal valve timing for
each driving condition and controls the camshaft timing oil control valve. In addition, the engine ECU
uses signals from the camshaft position sensor and crankshaft position sensor to detect the actual valve
timing, thus providing feedback control to achieve the target valve timing.
Summary of Contents for 1NZ-FE
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