Glow plugs are used in diesel engines to heat up the combustion chamber, making it easier to start the engine and keep it running until it reaches its ideal operating temperature. They are very common in buses, trucks, vans, tractors and other types of engines of all brands.

The diesel engine needs to compress the air in the combustion chamber and heat it to a very high temperature in order for it to start working. The glow plug facilitates this process and allows the engine to start quickly.

Unlike gasoline or alcohol engines that use spark plugs, glow plugs are used in diesel engines to raise the temperature of the air to the point of spontaneous combustion of the fuel at its compression ratio.

Glow plugs are used for two purposes: preheating the engine, when it is not yet running, and postheating, when the engine is already running but the outside temperature is too low.

This process reduces the level of pollutants and smoke in the environment, as well as reducing fuel consumption, in this case diesel, saving money and allowing the engine to perform more smoothly.