Intake Valve Timing Control Solenoid Valve
Intake valve timing control solenoid valve is activated by ON/OFF pulse duty (ratio) signals from the ECM.
Intake valve timing control solenoid valve controls the timing of intake valve opening/closing optimally by changing duty ratio depends on the driving conditions.
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Status of intake valve timing solenoid valve |
Intake valve timing controller activation |
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Engine OFF |
When starting the engine, the controller vane and sprocket are fixed in full retard position by the reaction force of return spring, improving the starting performance of the engine. |
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Active (Advanced angle) |
When the energization rate to the control solenoid valve is increased, the oil pressure from the oil pump is conveyed to the advance angle chamber of the controller. And retard angle chamber oil is drained. Accordingly, the controller vane rotates rightward and the phase of camshaft becomes advance angle. This condition brings about the greater overlap with the exhaust valve, enabling the exhaust gas cleaning by the internal EGR effect and the fuel consumption improvement by the reduction in pumping loss. |
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Neutral (Maintained) |
When it is the target valve timing, the energization rate to the control solenoid valve is adjusted to the intermediate state. The solenoid valve is positioned at the neutral position and the oil path is interrupted to maintain the cam shaft phase. |
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Return (Retard angle) |
When the energization rate to the control solenoid valve is decreased, the oil pressure from the oil pump is conveyed to the retard chamber of the controller. And advanced angle chamber oil is drained. Accordingly, the controller vane rotates leftward and the phase of camshaft becomes retard angle. |