Dual Coil Glow Plug

All glow plugs have the same purpose. The difference is quality! There are single coil and dual coil plugs. Single coil plugs will burn out if constant power is applied, while dual coil plugs will regulate their temperature and not burn out. dual coil regulates the plug's temperature to avoid catastrophic failures.
Dual Coil Glow plugs is plug with two heating elements instead of one. The extra coil allows the glow plug to have a "self-regulating" feature. This feature allows the dual coil glow plug to get very hot quickly for faster starts, but gives extended life at the same time.
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