What Are Glow Plugs and What Do They Do?

Jul 2, 2019

What Are Glow Plugs and What Do They Do?

If you have only ever owned petrol cars, the chances that you have come across glow plugs or know what they are is slim. Glow plugs are only ever used in diesel cars; however, they do have the same function as spark plugs.

What do glow plugs do?

Glow plugs are designed to act like small heaters which live inside the bonnet of a diesel-powered car. A glow plug takes the place of a spark plug in a petrol engine. Petrol fuel requires a spark to ignite a mixture of both air and fuel to start the engine. Whereas the diesel will combust in hot-air pressure. Glow plugs are not necessary all the time especially when there’s hot weather, as this means the fuel has the capacity to do this on its own, without the need for other car parts.

That being said, when we are experiencing cold weather it is harder for diesel fuel to ignite and prevents the fuel and air mixture from starting the engine. Therefore, a glow plug is needed as it acts increases the temperature of the diesel, so it can ignite.

What are the symptoms of bad glow plugs?

If your glow plugs are failing, driving your car will become very difficult. Be sure to know the signs and symptoms of worn-out glow plugs if you’re a diesel car owner because it prevents you from breaking down.

  • Your car will be hard starting if the glow plugs are failing, after checking if it’s the battery or fuelling system that’s causing the problems, check the glow plugs!
  • If you drive a modern car, you will most likely have a light on your dash that will alert you to a problem with the glow plugs.
  • Your car may feel strange to drive, the engine could even misfire as you drive along.
  • White smoke coming from the exhaust can indicate a glow plug that has become disconnected.

Who can replace my glow plugs?

If you have been reading this and believe you have an issue with your glow plugs, fear not as here at MyCarNeedsA.com, all you need to do is enter your reg number and we can gather quotes for local mechanics in your area. All you need to do is pick which one is best for you!

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