| 摘要 |
PURPOSE:To check deterioration in a catalyzer, by installing a detector detecting a suction air quantity and a temperature sensor detecting the outlet gas temperature of a catalystic converter. CONSTITUTION:A bypass passage 20 bypassing both upstream and downstream sides 3 and 4 of a throttle valve 5. A temperature sensor 8 detecting the outlet gas temperature of a catalytic converter 7, an oxygen content detector 9 and a p ressure sensor 10 detecting pressure inside a suction manifold 2 are all connected to an electronic control unit 11. When a suction air quantity is less than the preset quantity as well as when exhaust gas temperature is less than the preset one, an opening area of a flow control valve 22 is increased wide. Thus, the discharge of uncombustive HC can be held done to a low level so that a catalyzer is prevented from deterioration. |
