| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an air-fuel ratio controller for an internal combustion engine for an outboard motor capable of controlling an air-fuel ratio to an air-fuel ratio other than theoretical air-fuel ratio with high precision even by using an O<SB>2</SB>sensor changing its output characteristic in the vicinity of the theoretical air-fuel ratio. <P>SOLUTION: Amount of fuel injection is decided to control an air-fuel ratio of an engine to the theoretical air-fuel ratio by compensating basic amount of fuel injection by coefficient of feedback compensation decided based on output of the O<SB>2</SB>sensor. Learned coefficient KTIM of compensation is calculated based on the coefficient of feedback compensation (S208), and the calculated learned coefficient of compensation is substituted and updated only when pressure (engine load) in a suction pipe is in a predetermined scope for rotational speed of the engine (S210, S212, S214). When controlling an air-fuel ratio to an air-fuel ratio other than the theoretical air-fuel ratio, basic amount of fuel injection is compensated using the updated learned coefficient of compensation to decide amount of fuel injection. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
