From the theoretical air fuel ratio it is configurated by lean side the target air-fuel ratio is configurated on the basis

摘要

PROBLEM TO BE SOLVED: To provide an air-fuel ratio control method for an internal combustion engine maintaining the reduction of exhaust emission and the driving ability. ;SOLUTION: In this air-fuel ratio control method of an internal combustion engine, a target air-fuel ratio is set based on a catalyst temperature or the degradation of catalyst (S2). And also the target air-fuel ratio is guarded by a target air-fuel ratio guard value established based on the engine load (S3).;COPYRIGHT: (C)2001,JPO