| 摘要 |
PROBLEM TO BE SOLVED: To provide an alternative fuel concentration calculating system which can start calculating concentration of alternateive fuel in blended fuel under the condition that an air excess ratio is set at a first specified value in an internal combustion engine for burning the blended fuel with the air excess ratio set at a prescribed specified value. SOLUTION: An ECU 60, used in a two-wheeled motor vehicle 1, comprising an engine E in which blended fuel obtained by blending gasoline and ethanol is burned in a combustion chamber 23, and a fuel injection device for injecting a specified fuel injection amount which is set such that an air excess ratio in the combustion chamber 23 is a first prescribed specified value when the concentration of ethanol in the blended fuel is zero. The ECU 60 performs O<SB>2</SB>feedback control on the basis of an O<SB>2</SB>concentration obtained from an output from an O<SB>2</SB>sensor. The ECU 60 further calculates an actual fuel correction factor obtained by dividing a fuel injection amount after the O<SB>2</SB>feedback control by the specified fuel injection amount, and estimates the concentration on the basis of the actual fuel correction factor and the first specified value stored in the ECU 60. COPYRIGHT: (C)2010,JPO&INPIT |
