| 摘要 |
PURPOSE:To improve torque efficiency, by a method wherein two maps, in which the values of ignition times under a specified state are respectively written as an upper and a lower limit value, are prepared, and control of an ignition timing at a maximum lead angle in which knocking can be controlled within an allowable range is effected. CONSTITUTION:Two maps, in which a suction air pressure and the number of revolutions of an engine form parameter, are prepared in a ROM 17 in an MPU 18, by which an igniting device 21 is controlled according to the operating state f an engine. In the first map, the value of an ignition timing at an allowable maximum torque is written as an upper limit value, and in the second map, the value of an ignition timing at a limit being a maximum lead angle, by means of which knocking can be controlled within an allowable range according to spent fuel, is written as a lower limit value. During the occurrence of knocking, a division point is computed between the values of ignition times in address of the two maps selected according to the operating state, and the value of a correction ignition time is determined from the resultant value serving as a correction value, and a division point is changed according to a following knocking occurrence state. |
