Intake system for internal combustion engine

An intake manifold (34) of an engine (14) has a common pipe (38) disposed downstream of a throttle valve (42), a plurality of first through fourth branch pipes (36a through 36d) connected to the common pipe (38), and a bypass pipe (60) connected between the common pipe (38) and the first through fourth branch pipes (36a through 36d). The bypass pipe (60) has a plurality of branches (64a through 64d) connected respectively to the first through fourth branch pipes (36a through 36d). An amount of intake air flowing through the intake manifold (34) is detected by an air flow meter (74) disposed in the bypass pipe (60).