PURPOSE: To improve emission and fuel consumption by providing a communication passage which communicates independent intake passages of downstream side of a throttle valve with each other, and arranging a communication control valve controlled in its opening based on a required exhaust gas circulation quantity in an operation range where an engine has a sufficient output to spare at the communication passage.
CONSTITUTION: In a V type six-cylinder engine, independent intake passages 4a-4f are connected to intake ports 3 of the three cylinders 2 provided at banks 1a, 1b at both sides of an engine body 1. The end part of the upstream side thereof is connected to a surge tank 7. A throttle valve 8 is arranged on the way of independent intake passages 4a-4f. The passages 4a-4f of the downstream side are mutually communicated by the throttle valve 8 via a communication passage 10 at every banks 1a, 1b. A communication control valve 11 which opens and closes a communication condition is arranged at the communication passage 10. The communication control valve 11 is closed in a high load high speed range A and a extremely low load low speed range C, and is controlled to open at a particle load range B where an engine has a sufficient output to spare.
HITOMI MITSUO
MAMIYA KIYOTAKA
