A control device executes a feedback control operation of an electric motor such that a sensed opening degree of a valve approaches a target opening degree, which is set for a time of fully closing the valve. The control device stops the energization of the electric motor after reaching of the sensed opening degree of the valve to an energization stop opening degree, which is set on a valve opening side of a full closing degree of the valve in a valve opening direction of the valve. A return spring urges the valve in a valve closing direction of the valve. The target opening degree is set on a valve closing side of the energization stop opening degree in the valve closing direction.