MIVEC (Mitsubishi Innovative Valve Timing Electronic Control System)

MIVEC is a control system continuously varying the intake valve timing. The rotation angle of the camshaft does not change between the valve opening and closing.
System Configuration Diagram

MIVEC allows the optimum valve timing to be controlled in accordance with the engine operation and the idling stability to be improved, as well as the output and the torque to be better in all the operation ranges.

The engine-ECU assesses the engine operation through the signals from each sensor.
Based on the assessed information, the engine-ECU sends the duty signal to the oil feeder control valve and controls the spool valve position.
Changing the spool valve position allows the oil pressure to be divided into the retarded chamber and the advanced chamber, as well as allows the phases of the inlet camshaft and the exhaust camshaft to be continuously changed.

Phase Angle Detection

The detected phase angle is calculated using the cam position sensor signal.

Operation condition	Valve timing	Operation	Effectiveness
Within range of low speed and low load at idle		Overlap is decreased and amount of exhaust gas flowing back into intake port is limited.	Idle speed stable
Within range of low speed and high load at acceleration		Advancing closing timing of intake valve allows amount of intake air flowing back into intake port to be limited as well as allows volumetric efficiency to be improved, resulting in low and middle speed torques improved.	Low and middle speed torques improved
Within range of middle speed and middle load		Increasing overlap amount allows pumping loss to be decreased. Retarding opening timing of exhaust valve allows burned gas to work sufficiently and allows cycle efficiency to be improved, resulting in higher expansion ratio.	Fuel economy improved
Within range of high speed and high load		Retarding closing timing of intake valve in accordance with engine speed allows valve timing to be controlled according to inertia force of intake air and allows volumetric efficiency to be improved.	Output improved