Glow plugs

For a reliable cold start, even with low outside temperatures, diesel engines depend on the support of glow plugs.

The combustion cycles of a diesel engine basically correspond to those of a petrol engine. However, no spark plugs are required for the ignition of the air-fuel mixture.

The reason: diesel engines are self-igniting. Environmental air is suctioned in and compressed heavily in the cylinders. The compression ratio in this process is up to 25:1.

Through this compression the suctioned air reaches a temperature between 700 and 900 °C. If fuel is now added, it ignites solely on the basis of this heat.