ACTUATOR

INJECTOR

The injectors inject fuel in accordance with the actuation signals provided by the engine-ECU or engine-A-M/T-ECU. The fuel injection volume is controlled by the engine-ECU or engine-A-M/T-ECU in accordance with the signals provided by the crank angle sensor and the manifold absolute pressure sensor. One injector is provided for each cylinder, and the injectors are mounted on the cylinder head.
The delivery pipes deliver fuel to the injectors.
The nozzle of an injector contains 8 injection orifices that enable the injector to inject atomize fuel towards the two intake valves that are provided for each cylinder. This improves combustion efficiency and reduces the amount of HC (hydrocarbon) emissions when the engine is cold.

IGNITION COIL

The ignition coils generate high voltage that is required for igniting the spark plugs in accordance with the ignition signals provided by the engine-ECU or engine-A-M/T-ECU.
The engine-ECU or engine-A-M/T-ECU controls the ignition timing in accordance with the signals provided by the crank angle sensor and the manifold absolute pressure sensor.
An ignition coil, which is the plug-on type with a built-in power transistor, is provided for each cylinder, thus constituting an independent injection system. This system enables the ignition energy generated by the ignition coil to be supplied efficiently to the spark plug.

THROTTLE VALVE CONTROL SERVO

The throttle valve control servo, which is built into the throttle body, opens and closes the throttle valve in accordance with the signals provided by the engine-ECU or engine-A-M/T-ECU. The engine-ECU or engine-A-M/T-ECU determines the extent of the opening of the throttle valve in accordance with the signals provided by the crank angle sensor and the accelerator pedal position sensor, and controls the direction of current applied to the motor and its amperage.
The throttle valve control servo has adopted a highly responsive and energy efficient DC motor that uses small brushes.
The throttle valve holds its predetermined position when no current is applied to the throttle valve control servo. Thus, even if the current is disrupted due to a system malfunction, this system ensures the vehicle to be driven at a minimum level.

OIL CONTROL VALVE <135 engine>

The oil control valve, which is a solenoid valve that operates under duty cycle control, is mounted on the cylinder head. The duty cycle signals from the engine-ECU or engine-A-M/T-ECU cause the spool valve in the oil control valve to move in order to control the hydraulic pressure in the V.V.T. (Variable Valve Timing) sprocket.
The movement of the spool valve causes the engine oil from the cylinder block to be supplied to the advance chamber or the retard chamber at the V.V.T. sprocket, thus continuously changing the phase of the intake camshaft.
The engine-ECU or engine-A-M/T-ECU controls the oil control valve in accordance with the signals provided by the crank angle sensor and the manifold absolute pressure sensor.

Timing Advance
The engine-ECU or engine-A-M/T-ECU increases the ON duty cycle ratio to move the spool valve in the advance direction, thus increasing the amount of engine oil that flows into the advance chamber. This causes the V.V.T. sprocket to move in the advance direction.
Timing Retard
The engine-ECU or engine-A-M/T-ECU decreases the ON duty cycle ratio to move the spool valve in the retard direction, thus increasing the amount of engine oil that flows into the retard chamber. This causes the V.V.T. sprocket to move in the retard direction.
Holding
When the actual phase of the intake camshaft reaches the target phase, the engine-ECU or engine-A-M/T-ECU outputs an intermediate ON duty cycle ratio (holding duty cycle) in order to fix the spool valve in its intermediate position. This closes all the oil passages and establishes equilibrium in terms of the actual and target phases of the engine oil volume in the advance and retard chambers, thus holding the phase of the intake camshaft.