Glow plug with burnt tip
Examination
1. To check the glow plugs, disconnect the power supply line from the glow plugs.
2. Connect a test lamp (any 12 V bulb) with one terminal to the positive pole of the battery, and the other to the spark plug being tested, installed on the engine. If the bulb lights, the spark plug is working. If the bulb does not light, the spark plug is faulty and must be replaced.
Burning and failure of the glow plug is often the result of faulty injectors. If there is a burnt spark plug, then a simple replacement is not enough. It is necessary to check the injectors, including determining the shape of the spray torch, the operating pressure and tightness. It is important that the injector has a clear fuel cut-off.
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