| 摘要 |
PURPOSE:To maintain air-fuel ratio at a proper value so as to reduce the quantity of exhausted waste contaminant as much as possible by performing air-fuel ratio feedback control using an integration constant which is larger during transient operation of an internal combustion engine than while the engine is in its steady state. CONSTITUTION:During air-fuel ratio feedback control under transient operating conditions, a correction factor IMET(<1) for correcting an integration constant used for setting an air-fuel ration feedback correction factor alpha is set in proportion to the density of alcohol detected by an alcohol sensor 7. Next, a basic integration constant IO found by retrieval, etc., from a map according to engine speed N and a basic fuel injection quantity TF is multiplied by the correction factor IMET so as to set an integration constant (I) and then the air-fuel ratio feedback correction factor alpha is renewed by a value obtained by addition of the integration constant (I) to the previous value of the correction factor alpha, and then air-fuel ratio feedback control is started with the integration constant (I) being maximized in the same way as with gasoline in order to enhance responsiveness. |
