There is a larger vacuum hose, about 3/4 inch in diameter, leading down into the void between intake manifold runners 3 and 4. This larger hose, along with a narrow hose directly to the top of the throttle body, is connected to a plastic y-shaped piece that rests on top of the hose going down to the oil breather box beneath the manifold. Inside this plastic piece is the flame trap. Use a flashlight and lean over the passenger side of the engine to see this affair.