| 摘要 |
PURPOSE:To improve exhaust gas purging performance, by varying an air-fuel ratio feedback constant employed for calculation of an air-fuel feedback control signal in response to any change in a valve control timing produced according to operation condition of an engine. CONSTITUTION:A controller 66 is provided for calculating a control signal from a motor 60 varying a suction valve timing through variation of the phase of a suction cam shaft 42 in relation to a crank shaft, and an injection time signal which is corrected from a basic injection time, obtained from the outputs of an airflow meter 14 and a rotary angle sensor 34, by means of an air-fuel ratio feed-back control signal provided according to an air-fuel ratio feedback constant. The controller 66 varies said constant through reading-out of a required lag time from the map of a lag time according to a change in a valve control timing and in correspondence to a valve control timing, the rotational speed of an engine, and the amount of the air sucked during one complete turn of an engine, that may stay in allowable range respectively. |
