System for controlling air-fuel ratio in an internal combustion engine

摘要

A system for controlling the air-fuel ratio in an internal combustion engine provided with a fuel injector. The system has an O2 sensor for issuing signals on two levels, one corresponding to a high air-fuel ratio, the other to a low air-fuel ratio, and a feedback control device responsive to the signal from the sensor. The feedback control calculates a correction factor for maintaining the air-fuel ratio to a desired value during steady operation and for indicating the deviation in the ratio from the desired value during transient conditions. This deviation is employed to generate a transient correction value which is selected to minimize the deviation during transient conditions.