| 摘要 |
PURPOSE:To maintain proper value of air-fuel ratio regardless of variation of alcohol concentratin for internal combustion engines which use gasoline containing alcohol as fuel by increasing fuel injection quantity in relation to increase in concentration of alcohol in fuel. CONSTITUTION:In such engines as fuel which is injected from an electromagnetic fuel injection valve 14 is delivered to and burned at the combustion chamber 9 with air flow controlled by a throttle valve 4 which is linked with the accelerator pedal, excessively rich fuel-air mixture is required under a condition at low temperature or with the throttle valve fully opened. Under operational conditions other than the above-mentioned, employed is the closed loop control of fuel injection quantity by output from air-fuel ratio sensor 24, but this control mode is then to be discontinued and converted to the open loop control, whereby fuel inujection quantity is corrected corresponding to concentration of alcohol in a manner in which output from an arithmetic unit for basic injection quantity in the electronic control unit 15 is multiplied by a value related to output from an alcohol sensor 25 in a fuel line 29. |
