| 摘要 |
PURPOSE:To achieve normal operation of an O2 sensor by cooling the O2 sensor when the O2 concentration of an O2 sensor is smaller than actual O2 concentration of atmosphere around the O2 sensor or O2 concentration at the exhaust side of the O2 sensor. CONSTITUTION:A CPU 34 reads an electromotive force V as the output value of an (53 sensor 36. When the electromotive force V is negative, it indicates that a rustproof agent and other gas substances entered the inside of the sensor 36. For suppressing the gasification of them, a cooling device for cooling the sensor 36 is activated. The cooling device may commonly use a fan 44 for cooling a radiator to cool the sensor 36 or an exclusive cooling fan may be provided. The CPU 34 may stop operation of a heater 42 for the sensor 36 instead of the operation of the cooling device, thus preventing temperature increase in the sensor 36 or the amount of fuel injection from a fuel injection valve 26 and the opening of a throttle valve 28 may be controlled in a direction where mixed air becomes rich. When the electromotive force V is positive, it is not necessary to cool the sensor 36. |
