| 摘要 |
<p>PURPOSE:To rapidly detect the anomaly of a secondary air introducing device by judging the generation of anomaly if the average value of the air fuel ratio correction coefficient supplied from an air fuel ratio feedback device is below a prescribed value, when the secondary air introducing device for supplying the secondary air into an exhaust system operates. CONSTITUTION:An air fuel ratio controller is equipped with an air fuel ratio feedback device 5 which controls the fuel quantity supplied into an engine on the basis of the air fuel ratio signal supplied from an air fuel ratio detector 4 arranged din an exhaust passage 3. Further, the controller is equipped with a secondary air introducing device 6 equipped with a secondary air control valve 8 which supplies the secondary air into the exhaust passage 3 from an intake passage 2, bypassing an engine 1, in the case when the engine temperature is low. In this case, an operation judging means 9 for judging the presence of the control valve operation signal supplied from the secondary air introducing device 6 is provided. When the secondary air introducing device operates, an anomaly judging means 10 judges anomaly when the average value of the air fuel ratio correction coefficient which is supplied from an air fuel ratio feedback device 5 is below a prescribed value, and an alarm signal is generated.</p> |
