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Glow Plug System

Engine starting is aided by a solid state glow plug system. Function of this system is to pre-heat the combustion chamber to aid ignition of fuel.

System consists of 8 glow plugs, controller module, power relay, "WAIT TO START" indicator light and a wiring harness. Power relay is mounted on top of controller module circuit board. Complete assembly is mounted to rear of intake manifold.

Glow plugs are threaded into each combustion chamber. Glow plugs are small heaters that assist in cold starting. The glow plug controller and relay cycle voltage to these heaters, which causes them to heat rapidly. After the engine starts, the glow plugs continue to cycle during initial engine warm-up.

Fig 1: Glow Plug Test Connections
G72707Courtesy of FORD MOTOR CO.