| 摘要 |
PURPOSE:To quickly correct the decrease in the idling rotational frequency of an internal-combustion engine in a method of controlling the idling rotational frequency, by performing simple control of opening and closing a by-pass for a throttle valve to regulate the idling rotational frequency. CONSTITUTION:The time from the entry of the rotational frequency NE of an engine into a region (780rpm<=NE<=950rpm) higher than an upper limit, to the closing of a by-pass for a throttle valve, is shortened depending on the magnitude of the difference between the rotational frequency and the upper limit. The time from the entry of the rotational frequency NE into a region (550rpm<=NE<= 630rpm) lower than a lower limit, to the opening of the by-pass, is shortened depending on the magnitude of the difference between the rotational frequency and the lower limit. It is judged whether a count C2 has exceeded a prescribed value A (32msec, for instance). If it is judged so, the by-pass is opened. If the count C2 is lower than the prescribed value A and another count C1 is higher than a prescribed value B, the by-pass is closed. |
