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How Long Does a Glow Plug Last?

glow plugs

A diesel engine is a very powerful and complicated piece of machinery. There are a variety of things that have to work together in order for the diesel engine to fire off and run as intended. Just like a gasoline engine, the diesel engine will need a spark to initiate the combustion process. Without this spark, the diesel engine will not be able to fire and run. The glow plug releases a small spark of electricity when the key is turned over. Every time that the diesel vehicle is started, the glow plugs will have to do the job they are intended for. However, while a gasoline engine needs the spark plugs to fire continuously during operation, a diesel engine uses compression and heat, not the glow plugs, to maintain combustion.

The glow plugs on a diesel engine will usually last around a 100,000 miles but can fail before then. Making sure that the right quality glow plugs are put in your vehicle is important in keeping it consistent and reliable. When the glow plugs begin to fail, there will be a variety of different issues that may arise. Neglecting to act when signs of glow plug trouble arise can leave you stranded. The longer that you wait to have the glow plugs replaced, the more damage you will have to contend with. The time that is put into getting the right professional help will be worth it considering the functionality a new set of glow plugs can provide. Due to the constant use that the glow plugs in an engine get, it is easy for them to become worn over time. In most cases, the glow plugs on a diesel vehicle will not get much attention until they are malfunctioning. It is your job to make sure that the signs of worn glow plugs are noticed and that you act quickly to get them replaced.

The following are some of the signs that you will notice when it is time to have your glow plugs replaced:

  • The diesel vehicle is hard to start during cold weather
  • There is more smoke coming from the vehicle than normal
  • The diesel engine is misfiring on a regular basis
  • Decreased fuel efficiency

Having a professional replace the glow plugs is your best course of action due to the complexity that is involved in this process.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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