| 摘要 |
PURPOSE:To make variations in an air-fuel ratio absorbable as well as to improve driving performance, by letting a control unit carry out feedback control at the specified time just after the end of engine warming up, etc., while causing deflection between a theoretical air- fuel ratio and a set air-fuel ratio to be learned and stored in memory according to the amount of air-fuel ratio feedback compensation at that time. CONSTITUTION:This method comprises an air-fuel ratio control unit 40 which controls an injector 26 with a valve opening time signal to be found in accordance with the output, etc., of a suction air quantity sensor 16 and an engine speed sensor 28. And, likewise this air-fuel ratio control unit 40 performs lean control which makes an air-fuel ratio into feedforward control so as to cause the air-fuel ratio to come more adjacent to the lean side than a theoretical air- fuel ratio and partial lean control which switches the feedforward control and the conventional feedback control to each other according to a state of driving. At this time, the control unit 40 further forces the feedback control to be carried out at the specified time just after the end of engine warming up or just after the end of engine starting and is constituted so as to cause deflection between the theoretical air-fuel ratio and the set air-fuel ratio to be learned and stored in a memory according to the amount of air-fuel ratio feedback compensation at this time. |
