Control system for a throttle plate

The present invention relates to an electronically controlled throttle device comprising a throttle valve (2) held rotatably in a throttle body (1); an actuator (5) for driving the throttle valve (2); a return spring (11) which gives a force to return the throttle valve (2) in the full open direction; a throttle position sensor (10) for detecting the opening of the throttle valve (2); and a throttle actuator control unit (200) for driving the actuator (5) based on the opening of the throttle valve (2) detected by the throttle position sensor (10) and a target opening. The throttle actuator control unit (200) is provided with a control means (216) which controls the actuator (5), when EGR control or DPF control has ended, so that the throttle valve (2) turns toward the full open position in a longer period of time than the length of time in which the throttle valve (2) is turned toward the full open position by the return spring (11) only.