Patent ID: 6405697
Filing Date: 2002-06-18
Classification: F01L,F02D,Y02T

Abstract:
A valve characteristic control apparatus of internal combustion engine, comprising:a camshaft provided with a three-dimensional cam having a cam profile that continuously changes in a direction of an axis of the cam; a valve lift-varying mechanism that allows amount of valve lift of an engine valve to be varied in accordance with a displaced position of the camshaft in the direction of the axis of the cam; a sensor that detects an actual amount of valve lift and outputs a signal; and a controller that receives the signal from the sensor and diagnoses that there is an abnormality of the valve lift-varying mechanism, provided that a deviation between the actual amount of valve lift and a target amount of valve lift of the engine valve is greater than a predetermined value and that an amount of change in the actual amount of valve lift is less than a predetermined change value.