| 摘要 |
PURPOSE:To stop feedback control of air-fuel ratio at the time of increasing or decreasing fuel supplied to cylinders forcibly when engine is accelerated or decelerated during feedback control of air-fuel ratio and to recommence the feedback control smoothly by setting an air-fuel ratio controlling signal at a level corresponding to the mean value of the control width. CONSTITUTION:A control unit 14 is furnished with an engine speed signal from an ignition circuit 12 in addition to output signals of an air flow meter 7, O2- sensor 8, water temperature sensor 9 and throttle sensor 15. On the basis of these signals, the control unit 14 controls the opening time of a fuel injection valve 20. In case that it is judged at a step 102 that conditions of feedback control are satisfied from the above signals and at the same time it is judged at steps 104, 106 that neither fuel increasing control nor fuel decreasing control is executed, the quantity of feedback control is determined at a step 108. Further, in case that the conditions of feedback control are not satisfied or when fuel increasing or decreasing control is effected, feedback control on the air-fuel ratio is stopped at a step 112, and the air-fuel ratio controlling signal VF is set at a voltage level corresponding to the mean value of the control width of feedback control, thus completing the entire program at a step 110. |
