A bistable fluidic switch is switched from its stable state by a pin inserted in the power nozzle of the bistable fluidic switch, the pin being controlled by an electromagnetic actuator which is controlled from an electronic computer. The fluidic switch element has a cross-over type interaction region and a common outlet leading to a pair of output passageways, one of which returns fuel to the supply tank, and the other of which leads to the air intake manifold of the engine. Air is introduced into the output passageway leading to the engine so as to air atomize the fuel before injection of same into the air intake manifold.