| 摘要 |
PURPOSE:To prevent depreciation in output and fuel consumption of an engine by suspending learning control during the abnormality of a knock sensor, and by performing open loop control at the ignition timing based on a knocking limit of a gasoline of low octane number. CONSTITUTION:A control unit 30 inputs each detection signal from each sensor 20-22, 26 by which an engine driving state is detected, and outputs a predetermined control signal to which a predetermined operation is processed, to an igniter 27. The abnormality of a knock sensor 26 is judged by a means 47. Based on engine rotation, suction pipe pressure, and so on, calculated by means 31, 32, ignition timing for abnormal occasion is set by a means 48. The ignition timing for abnormal occasion is input to a means 49, along with normal ignition timing calculated by a means 38. At the abnormality of the knock sensor 26, the ignition timing for abnormal occasion is selected by a means 49, and is output to a means 39 that drives the igniter 27. |
