AIR-FUEL RATIO PRESUMING DEVICE FOR EACH CYLINDER OF INTERNAL-COMBUSTION ENGINE AND CONTROL DEVICE

摘要

PROBLEM TO BE SOLVED: To enhance the presumptive accuracy of the air-fuel ratio of each cylinder by an observer and implement the feedback control of the air-fuel ratio using the obtained estimate. SOLUTION: In case the number of combustion history to be taken into consideration with an internal-combustion engine is three or more, the weighting factor of the weighted mean for the prior combustion history excluding the combustion history more than two immediately before and less than the mentioned number of combustion history to be taken into consideration is made zero. Estimate is used for feedback control of the air-fuel ratio.