| 摘要 |
PURPOSE:To prevent improper idling speed control by making necessary feedback control on the basis of a feedback correction value and a learning value, and prohibiting the setting of a new learning value when the abnormality of an air-fuel ratio sensor is detected. CONSTITUTION:When the operation condition of an engine is in idling state, a feedback correction value setting means B sets a feedback correction value about a control factor to cause the change of an engine speed depending upon a difference between an engine speed detected by an engine speed detecting means A and a target idling engine speed. And a learning value is set with a learning value setting means C, depending upon the feedback correction value. Also, feedback control is made by a revolution control means D on the basis of the feedback correction means and the learning value. On the other hand, the feedback control of an air-fuel ratio is made by an air-fuel ratio control means F on the basis of output from an air-fuel ratio sensor E. In this case, when the abnormality of the sensor E is detected by an abnormality detecting means G, the setting of a new learning value with the means C is prohibited by a learning prohibit means H.
|
