| 摘要 |
PURPOSE:To prevent the aggravation of drivability upon an open loop control due to the variability and the deterioration of the characteristics of the air-fuel ratio control system by a method wherein the control signal of the open loop control is corrected by referring to the control signal of a feedback control. CONSTITUTION:D'o, which is an average value (D1+D2)/2 of time rates D1, D2 to control an electromagnetic fuel valve upon stabilized time of the feedback control (standard; 14.7), is memorized into a memory. When the feedback control is transferred to the open loop control upon accelerating or the like and the air- fuel ratio is controlled to a rich side lambdax, the time rate D'x, corrected as a result of an operation D'x=Dx-(Do-D'o), is decided, Here, Dx is a standard objective time rate upon the open loop while (Do-D'o) is a deviation from the standard objective value Do of the time rate upon the feedback. According to this method, the variability and the deterioration of the air-fuel ratio characteristics may be corrected even upon the open loop control and the desired air-fuel ratio lambdax may be obtained. |
