摘要 |
<p>An air-fuel ratio control device has an open loop controller which controls an air-fuel ratio to be a target air-fuel ratio, a feedback controller that shifts the target air-fuel ratio to a logical air-fuel ratio, and feedback controls the air-fuel ratio to be the logical air-fuel ratio by using a feedback correction coefficient determined based on an output of an O2 sensor, an average value calculator that calculates an average value of the feedback correction coefficient when the output of the O2 sensor reverses from a lean side to a rich side and from the rich side to the lean side in a feedback control by the feedback controller, and a learned value calculator that calculates a learned value based on the average value at a time when the average value calculated by the average value calculator becomes substantially constant.</p> |