摘要 |
An air-fuel ratio controller of an internal combustion engine which can perform air-fuel ratio control with characteristics suitable for each operation range when the air-fuel ratio control of the internal combustion engine is performed, and is directed particularly to improve control response and to eliminate an erroneous operation. When a fuel correction quantity is set in accordance with the difference DELTA (A/F) between a measured air-fuel ratio (A/F)i and a target air-fuel ratio (A/F)OBJ, the controller of this invention is designed so that the fuel correction quantity is limited in accordance with limit values KLMIN, KLMAX, KRMIN, KRMAX corresponding to the target air-fuel ratio. Therefore, the engine which is subjected to fuel supply control by the target fuel quantity TINJ based on this fuel correction quantity is operated with optimum characteristics for each operation range, can particularly improve response, can reliably reduce a knock in a knock occurrence zone, can prevent engine trouble and breakage and exhaust gas deterioration resulting from erroneous operation during the air-fuel ratio control, and can prevent stalling of the engine. <IMAGE> |