LEARNING AND CONTROL APPARATUS FOR ELECTRONICALLY CONTROLLED INTERNAL COMBUSTION ENGINE

A learning and control apparatus for an electronically controlled internal combustion engine having such an object of control as the air-fuel ratio in an air-fuel mixture or the idle rotation number of the engine wherein a pulse duty signal corresponding to a basic control value is set according to engine driving states. The basic control value is corrected by adding an appropriate correction value to the basic control value. Feedback control is carried out so that the actual controlled value is made to follow the aimed control value, and a learning correction quantity is computed by learning said feedback control so that the feedback control amount is set as small as possible. Since the new learning correction quantity is restricted by the preceding learning correction quantity, forcibly increasing or decreasing a control value which is computed based on said ordinary learning correction quantity when difference between the preceding and present learning correction quantities is larger than a predetermined value is executed, thereby controlling the object of control without time-lag is obtained effectively if the control value to be controlled is abruptly changed.