| 摘要 |
PURPOSE:To enable highly precise control of an air-fuel ratio, by storing two data for respectively determining the quantities of the fuel fed when an EGR is brought to an ON and an OFF state, and obtaining the quantities of the fuel fed, which are optimum at the time when the EGR is brought to an ON and an OFF time, based on said data. CONSTITUTION:A part of exhaust gas is caused to flow back to the downstream side from a throttle valve 4 in a suction pipe 3 through an exhaust branch pipe 11, an EGR valve 12, and an EGR duct 13. In said device, the opening closing of the EGR valve 12 is controlled through a negative pressure regulated by a control valve (electromagnetic valve) 9 which is controlled by a fuel control part 8, based on the outputs of an absolute pressure sensor 6 and a detecting means 7 for the number of revolutions (ignition coil). Namely, if, from the output of an EGR range deciding device 16, it is decided that the EGR is in an OFF state, the control valve 9 is brought to an inoprative state, and simultaneously, based on data from a fuction generator 26, the driving time of an electromagnetic jet valve 5 is decided. Further, when it is decided that the EGR is in an OFF state, the control valve 9 is brought to an operative state, and simultaneously, based on data from a function generator 28, the driving time of the jet valve 5 is decided. |
