An intake air flow rate control method system for an internal combustion engine includes a valve which is provided with an electromagnetically operated actuator responsive to a control signal. The control system identifies a control signal for controlling actuation of the actuator and thereby for controlling the air flow rate generating the control signal indicative of the control. The display selectively carries out closed loop (feedback) control and open loop control corresponding to engine driving conditions. Feedback control is carried out when the engine driving condition is stable (in steady state). To determine a suitable condition control for closed loop, a throttle valve closed position, a transmission neutral, and a vehicle speed are checked. When the throttle valve is closed and the transmission is in neutral, the vehicle speed is less than 8 km/h and/or the fuel supply occurs shut off, a decision to carry out feedback (closed loop) control is made. Thus, according to the present method and system, control of the air flow rate can be effectively and successfully switched corresponding to engine driving condition.