Glow plug with burnt tip
To check the glow plugs, disconnect the power bus from the plugs. Connect a test lamp (any 12 V bulb) with one terminal to the positive pole of the battery, and the other to the plug being checked installed on the engine. If the bulb lights up, the plug is working. If the bulb does not light up, the 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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