| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an exhaust emission control device which is excellent in a trouble detection of a switching means. SOLUTION: This device has a reflex channel 35 to the upstream of a catalyst device 21, and a fault diagnostic device 10 has a temperature detection means 11 in the downstream of an absorber 22, temporaily switches an operating state when a switching valve is in a stationary operating state and decides the property of the switching valve based on the difference valve of temperatures before and after the switching. Or the device has a reflex channel 35 to an engine intake side, and the fault diagnostic device 10 has a temperature detection means of the reflex channel 35, temporarily opens and closes the reflex channel 35, decides the propriety of the switching means of the reflex channel 35 based on the temperature detection value before and after the switching. Or, the temperature detection means 11 is provided in the upstream of the switching valve, the reflex channel 35 is opened/closed in a state that the exhaust channel of the adsorber 22 is closed and the propriety of the switching valve is decided based on the temperature detection value in the upstream of the switching valve before and after the opening and closing of the reflex channel 35.</p> |
