PURPOSE: To prevent drop of torque and feedback mis-control of an air-fuel ratio respective, by increasing an intake gas quantity at the time of controlling as lean air-fuel ratio, and suppressing feedback control of the air-fuel ration at the time transfer from the rich side to the lean side of the air-fuel ratio.
CONSTITUTION: A throttle valve 4 and a fuel injection valve 5 are arranged in the intake air passage 2 of an engine 1. On the other hand, a bypass control valve 7 is arranged in a bypass passage 6 which bypasses the throttle valve 4. The throttle valve 4, the fuel injection valve 5 and the bypass control valve 7 are controlled by a control unit 12 based on respective detection signals from respective kinds of sensors 3, 8, 11 which detect an operation condition of the engine 1, respectively. In this case, only a specified intake air quantity is increased by the control unit 12 at the time of control toward the lean air-fuel ratio. Feedback control of the air-fuel ratio is suppressed for specified period at the time of transferring the air-fuel ratio from its rich side to its lean side.
| JPS51114528 | FUEL CONTROL DEVICE IN INTERNAL COMBUSTION ENGINES |
| WO/1983/001655 | ELECTRONICALLY CONTROLLED FUEL INJECTION DEVICE |
| JPS59192838 | AIR-FUEL RATIO CONTROLLING METHOD |
TOKUDA YOSHIHARU
MATSUNAGA TAKAO
NISHIOKA FUTOSHI
