| 摘要 |
<p>PURPOSE: To provide the controller of an internal combustion engine which can detect the failure of an exhaust by-pass valve mechanism, by judging, as the operation failure of an exhaust by-pass valve, one of such states when the reversal cycle of the output of an exhaust gas concentration sensor is shorter/-longer than a predetermined reversal cycle when an engine is/is not under its starting condition. CONSTITUTION: The controller of an internal combustion engine reads in an output value from a LAF sensor 15, detects that an engine 1 is switched to a starting mode, and judges, as the operation failure of an exhaust by-pass valve 19, when a reversal cycle between the lean/rich sides of the output of an exhaust gas concentration sensor 18 is shorter than a predermined cycle. Also, as the same above, the controller reads in the output value from the LAF sensor 15, detects that the engine 1 is not switched to the starting mode, and judges, as the operation failure of the exhaust by-pass valve 19, when the reverse cycle is longer than the predetermined cycle. And, the controller judges one of these judgements as the failure. Hereby, the failure of the operation mechanism of the exhaust by-pass valve 19 can be detected certainly.</p> |
