Patent ID: 6439175
Filing Date: 2002-08-27
Classification: F02D,Y02T

Abstract:
A control apparatus for an internal combustion engine, comprising:a variably operated intake valve enabled for its open-and-closure operation to be arbitrarily controlled; a target air quantity calculating section that calculates a target air quantity to be sucked into an engine cylinder on the basis of an engine driving condition; a target vacuum pressure calculating section that calculates a target vacuum pressure on the basis of the engine driving condition; a throttle valve controlling section that controls a throttle valve disposed in an intake air passage of the engine to achieve the target vacuum pressure; and an intake valve open-and-closure timing controlling section that calculates and controls valve open and closure timings of the variably operated intake valve to achieve the target air quantity, wherein the valve closure timing of the variably operated intake valve is varied in accordance with a vacuum pressure developed within a portion of the intake air passage which is located downstream to the throttle valve so as to compensate for variation in air density in the portion of the intake air passage located downstream to the throttle valve.