| 摘要 |
PURPOSE:To attain a good drivability, by changing feedback control for lean control when the load upon an engine has been lower than a judgment value for a prescribed time after dropping below a prescribed value. CONSTITUTION:An air-fuel ratio control circuit 61 comprises a CPU61a, which receives the outputs of various sensors to control machinery required, an ROM 61b, in which necessary numerical values and programs are previously stored, a RAM61c, in which numerical values and flags in processes of calculation are stored in prescribed regions, an A/D converter 61d, an input/output interface 61e, a backup memory 61f, which is supplied with electricity from an auxiliary power source at the stoppage of an engine to keep memorization, and a bus line 61g. The load upon the engine is compared with a first judgment value and with a second judgment value lower than the former. When the load is less than the first judgment value, lean control is changed for feedback control. When the load is less than the second judgment value, the feedback control is changed for the lean control. In these cases, the load is detected at only one prescribed point. |
