Fuel Injector
Fuel injector is mounted in throttle body so that fuel from injector is directed into incoming air stream. While power to injector is supplied by power module, it is controlled by indirect signal from logic module. When electric current is supplied to injector, an integral armature and pintle valve move a short distance against a spring, opening a small orifice.
Fuel supplied to injector is forced around pintle valve and through this opening, resulting in a fine spray of fuel in the shape of a hollow cone. A constant pressure is maintained across injector (by pressure regulator), so the length of time that this opening is maintained (injector "ON" time) determines the amount of fuel entering engine.