| 摘要 |
PURPOSE:To prevent the breaking of an O2 sensor due to the freezing of water- drops attached, in a device in which exhaust gas recirculation quantity is controlled on the basis of the detected value of the O2 sensor provided on an intake pipe, by electrifying the heater for heating the O2 sensor for a prescribed period of time after the stoppage of the engine. CONSTITUTION:On the basis of the detected values of a revolution detector 15, an air temperature detector 10, an intake air quantity detector 8, and an O2 sensor 4, an electronic controller 16 feedback-controls an exhaust gas recirculation control valve 12 so that an optimum exhaust gas recirculation quantity in response to the operating conditions can be obtained. When the temperature of intake air is less than 0 deg.C, the electronic controller electrifies a heater 5 to prevent the O2 sensor 4 from being wetted with water vapor. |
