Idling speed feedback control method for internal combustion engines

摘要

A method of controlling the operating amount of a control valve for regulating the quantity of supplementary air being supplied to an internal combustion engine, in a feedback manner responsive to the difference between a desired idling speed and an actual engine speed, while the engine is in a predetermined idling region. When the engine is in a predetermined decelerating region immediately preceding the predetermined idling region, a basic value of the operating amount of the control valve is corrected in dependence upon a detected value of the engine temperature and a detected value of the decreasing rate of the engine speed. When the engine is further decelerated into the predetermined idling region, the feedback control is started by applying the corrected basic value of the operating amount of the control valve as an initial value thereof. Preferably, when the engine is in the predetermined decelerating region, the operating amount of the control valve is set to a value equal to the initial value applicable at the start of the feedback control, and supplementary air is supplied to the engine in a quantity corresponding to the set operating amount of the control valve.