| 摘要 |
<p>An exhaust gas recycling device allowing the exhaust system of an internal combustion engine to communicate with the downstream side of a throttle valve in an intake system through an exhaust gas recycling passage, wherein the opening of a control valve installed in the exhaust gas recycling passage is controlled to regulate the recycled amount of exhaust gas recycled from the exhaust system to the intake system; a failure diagnosing device for the exhaust gas recycling device, wherein, when specified failure diagnosis requirements are satisfied, the control valve is drivingly controlled so that the opening thereof is varied gradually, the amount of variation in sucked air or amount of variation in sucked air pressure in a specified period after the start of driving control of the control valve is detected and, when the detected value does not exceed a specified judgment value, the exhaust gas recycling device is diagnosed to have a failure.</p> |
