Glow Plugs

Glow plugs are threaded into each cylinder combustion chamber. Glow plugs are small heaters that assist in cold starting. The glow plug controller/relay (mounted on top-rear of engine) cycles 12 volts to these 6 volt heaters, which causes them to heat rapidly. After the engine starts, glow plugs continue to cycle on and off for about 25 seconds, depending on coolant temperature.