Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Ignition System (Service Information): Plug-Glow: Operation
The glow plugs are used to preheat the combustion chambers in order to achieve the ignition temperature required for the fuel-air mixture.
The glow plug consists of a housing with a female thread and an interference-fit rod. The heating element is integrated in the glow rod. It consists of a heating winding and a control winding connected in series.
When the glow plug system is switched "ON", a current of about 30 ampere flows to each glow plug. The heating winding heats the glow plug. The control winding increases its resistance as the temperature rises and limits the current to approximately 15-25 ampere. The glow plug is protected this way from overloads.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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