| 摘要 |
The purpose of the present invention is to accurately control an exhaust air-fuel ratio even when a waste gate valve (40) is being operated. An ECU (60) is provided with a turbine passage route constant (At) corresponding to a time required by exhaust gas to flow via a turbine (36a) of a turbocharger (36) to an air-fuel ratio sensor (56), and a bypass route constant (Ab) corresponding to a time required by the exhaust gas to flow via a bypass channel (38) to the air-fuel ratio sensor (56). The ECU (60) calculates first and second fuel injection correction amounts (?t and ?b) reflecting the route constants (At and Ab). When air-fuel ratio feedback control is implemented, one of the fuel injection correction amounts (?t and ?b) is selected on the basis of at least an open/close state of the waste gate valve (40), and the amount of fuel injection is corrected by using the selected fuel injection correction amount. Thereby, differences in the length of exhaust route or air-fuel ratio variations due to the opening or closing of the waste gate valve (40) can be appropriately compensated. |
