| 摘要 |
An apparatus for use with an internal combustion engine operable on either of gasoline fuel, alcohol fuel and gasoline/alcohol fuel blend. The apparatus comprises an alcohol concentration sensor for producing a signal indicative of an alcohol concentration of the fuel to be delivered to the engine, an oxygen sensor for producing a signal indicative of an oxygen content of exhaust gases discharged from the engine, and an engine coolant temperature sensor for producing a signal indicative of an engine coolant temperature. A control unit is coupled to the alcohol-concentration, oxygen and engine-coolant-temperature sensors. The control unit is responsive to the air/fuel ratio feedback signal for correcting the fuel supplied to the engine to maintain a desired air/fuel ratio when the sensed engine coolant temperature exceeds a predetermined value. The control unit is also responsive to an idle engine condition for calculating a target value for engine idling speed as a function of alcohol concentration and engine coolant temperature when the coolant temperature is below the predetermined value. An engine speed control device is coupled to the control unit for adjusting the engine speed at the calculated target value. |
