| 摘要 |
PURPOSE:To ovbiate roughness while keeping emission in good condition, by turning an air-fuel ratio controlled variable to the mean value of a feed-back controlled variable at idling just prior to it when stopping the air-fuel ratio feedback control, in case of a stationary state at idling. CONSTITUTION:A control unit 20 receives detection signals from an intake-air quantity sensor 12, an O2 sensor 15, a revolution speed sensor 21. A water temperature sensor 22 and an intake-air temperature sensor 23, through which it controls a fuel injection valve 14. On the other hand, the control unit 20 judges a state of idling in relation to the car speed and throttle opening and, if the idling state comes into a stationary state upon a fixed delay, calculates the geometric mean value of a feedback controlled variable that takes in 2n times during the interval, securing the air-fuel ratio controlled variable to the mean value and stopping the air-fuel ratio feedback control. |
