However, when it is cold and frosty and the cylinder temperature is too low to ignite the fuel, the combustion chamber needs to be heated first, and that is the job of the glow plugs.
The glow plugs are electrical elements that are, depending on the temperature of the engine, activated by the vehicle’s control system. Although glow plugs have a significantly longer service life than spark plugs, they are one of the engine’s wear parts and need to be replaced a few times during the life of the engine. The engine has one glow plug per cylinder, and since they wear down equally, you should replace them all at the same time.
Common signs of glow plug failure:
- The engine is difficult to start when cold
- Idling is uneven after ignition
- Weak acceleration when the engine is cold
- Sooty smoke from the exhaust pipe when driving with a cold engine
Frequently asked questions about glow plugs
What is the difference between glow plugs and spark plugs?
Both spark plugs and glow plugs are located in the engine cylinder heads, but glow plugs are only used in diesel engines, while spark plugs are used in petrol engines.