| 摘要 |
PURPOSE:To prevent any effect caused by inconvenient characteristics of an oxygen density detector, by a method wherein a current of a given value is supplied to the oxygen density detector only when oxygen density in exhaust gas is in a thin range, and feedback control of an air-fuel ratio takes place based on a detected signal from the oxygen density detector under such condition. CONSTITUTION:A device is constituted such that an air-fuel ratio signal V0 is inputted to a control circuit 13 through a detector buffer circuit 12 for controlling a current fed to an oxygen density detector 11, a detected signal AF from a heat ray system air amount detector 14 installed in a bypass passage 2 as a load detecting means detecting the load fluctuation of an engine 8 is inputted to the control circuit 12, and when the control circuit 13 decides that the load fluctuation occurs and it is decided that the air-fuel signal V0 is dense, a current setting instruction signal I is outputted so that a current of a given value is outputted to the detector buffer circuit 12. |
