SUPERCHARGING PRESSURE CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE WITH SUPERCHARGER

PURPOSE:To provide a supercharging pressure control device for an internal combustion engine with a supercharger which is designed to prevent the abnormal increase of a supercharging pressure when a supercharging pressure is erroneously detected owing to abnormality of a pressure detecting means to detect a supercharging pressure, and prevent the occurrence of abnormality to an engine and a supercharger. CONSTITUTION:A supercharging pressure control device for an internal combustion engine with a supercharger comprises a supercharger 3, a supercharging pressure regulating valve 5 to regulate a supercharging pressure, a step motor 6 to drive the regulating valve, an ECU 7 to control the motor, and a PB sensor 18 to detect a supercharging pressur' The ECU 7 is operated to decide the occurrence of abnormality when, during feedback control, a difference between the actual opening of the supercharging pressure regulating valve 5 and the target opening of the supercharging pressure regulating valve according to a current operation state exceeds a set value and brings the opening of the supercharging pressure regulating valve 5 into an approximately full opening state. This operation causes the stop of supercharging to reduce a supercharging pressure.