| 摘要 |
PROBLEM TO BE SOLVED: To provide a suction and exhaust device for an engine equipped with a low-pressure EGR device, capable of precluding misfire on deceleration by supplying the air containing no EGR gas to a combustion chamber quickly on deceleration.SOLUTION: An intake manifold 3 is equipped with a main suction passage 8 composed of an inmani upstream passage 8a, a surge tank 8b, and a plurality of suction branches 8c, and a sub-suction passage 9 composed of a sub inmani upstream passage 9a to bypass the inmani upstream passage 8a and a plurality of sub-suction branches 9b branching from the sub inmani upstream passage 9a and bypassing the suction branches 8c, and on deceleration, an opening/closing valve 10 installed in the main suction passage 8 is closed. This allows the passage capacity of the suction air in the intake manifold 3 to be shrunk largely, and it is possible to preclude misfire on deceleration by changing over quickly the suction air inhaled to the engine from the air with EGR gas mixed into the air not containing EGR gas. |
