Patent ID: 6014963
Filing Date: 2000-01-18
Classification: F02D

Abstract:
A method for controlling an air-fuel ratio in an internal combustion engine wherein, in accordance with a detection signal from an exhaust sensor disposed in an exhaust passage of the internal combustion engine, a preset feedback control is made by a control means so that the air-fuel ratio becomes a target value, an operation zone is divided into a plurality of zones, and when an operating condition of the internal combustion engine has entered one of said zones, if said operating condition is a steady condition, and after the preset feedback control has been conducted, a learning control is made to update a correction value in said feedback control for the zone concerned, wherein:a stand-by function is added to said control means, and when the operating condition of the internal combustion engine has shifted between said zones, the learning control updates the correction value, after the shift is performed, in accordance with said stand-by function.