摘要 |
Fuel properties estimating apparatus for an internal combustion engine includes a controller to determine an estimated component concentration of a component such as alcohol in a fuel. The controller calculates a new value of the estimated component concentration in accordance with a component concentration variation and a stored previous value of the estimated component concentration. From an air-fuel ratio correction quantity calculated from an actual air fuel ratio, for correcting a fuel injection quantity, the controller calculates the component concentration variation by using a conversion function determined by the previous value of the component concentration. |