Control system for internal combustion engine

摘要

A control system for an internal combustion engine having at least one intake valve and at least one exhaust valve is disclosed. The control system includes a valve operating characteristic varying mechanism and a hydraulic control valve for controlling a hydraulic pressure to be supplied to the valve operating characteristic varying mechanism. The valve operating characteristic varying mechanism continuously varies an operating phase of the at least one intake valve and/or the at least one exhaust valve of the engine. A cleaning operation of the hydraulic control valve is performed in a predetermined operating condition of the engine. An intake air amount of the engine is controlled according to an operating condition of the valve operating characteristic varying mechanism when the cleaning operation of the hydraulic control valve is performed.