4 Reasons Your RC glow plug keeps burning out


RC glow plugs are one of the most important parts of your RC vehicle’s engine. They are the core of your vehicle and the reason why your RC can go as fast as you want it to go.

Why does my RC glow plug keep burning out?

Nothing kills the mood faster than your RC glow plug keeps burning out.
Once it burns out your vehicle won’t be able to start anymore and even if it does it will struggle to run at high speeds. The joy of an RC nitro engine is its speed, without that speed it’s just no fun. 

What causes a glow plug to burn out

Glow plug burnouts are a common struggle amongst RC hobbyists which is why it is important to know what causes it. 

There are 4 reasons why your RC glow plug keeps burning out:

  1. Your nitro engine is running too lean,
  2. Your plug temperature is not correct,
  3. The type of fuel mixture you use,
  4. You got dirt all over your RC engine.

Having information on what causes these burnouts will help you prevent them from happening or know how to solve them if they occur. There are many factors that can cause your engine to burn out. In this article, you will get a detailed list of the possible factors so you can know what to avoid.

1.  Running the nitro engine too lean

Nitro engines run on nitro fuel, which is a unique type of fuel that is a mixture of fuel and air.
To lean out a nitro engine you need to adjust the air/fuel mixture. A properly functioning engine needs a balanced level of fuel and air. This directs more air into the engine than fuel. 

This method increases the power of your vehicle but also causes your engine to overheat. You must be cautious when you are leaning out your engine or you run the risk of running the nitro engine too lean.
A lean motor engine will cause wear, and bad performance, and will also cause your glow plugs to burn out. 

It is the most common cause of glow plug burnouts in nitro engines.

2. A plug that is too hot or too cold

An overheated glow plug or a cold one can cause your glow plug to burn out completely. An extremely hot glow plug will harm your RC vehicle in several ways.
Overheating your RC motor engine is never a good idea because it blows out some of the crucial parts of your vehicle, including the glow plug. 

Hot glow plugs speed up the ignition time of your nitro engine but when it gets too hot, it can burn out the glow plug. When your glow plug is too cold, your vehicle will struggle to start. Your glow plug needs to be hot enough to ignite the fuel/air mixture in the combustion chamber but cold enough to avoid overheating the entire engine.

3. Type of fuel\mixture

The fuel mixture used for your nitro engine is unique to the model and using another type of fuel that is not approved by the manufacturer can have adverse consequences on your RC plug.
A fuel mixture that is not suitable for your engine can cause your glow plug to burn out. Selecting the wrong fuel can also make your engine rise to dangerous temperatures. If your nitro percentage is too high compared to your glow plug or the oil in the fuel/air mixture is too small then this could also burn out your glow plug. 

4. Dirt got in the engine

Dirt in the engine of your RC vehicle is another common factor that can make your glow plug burn out.

The dirt in your engine could be regular dirt or aluminum strained from the engine. This dirt needs to be removed as soon as possible and it can be removed by tuning your vehicle. If your RC nitro engine is properly tuned but it still keeps burning out your glow plug then try passing the fuel through your engine, after which take out your glow plug and then turn the engine upside down to let the dirt and fuel fall out.

How can you stop your RC glow plug from burning up?

To stop your glow plugs from constantly burning up, you can tune your vehicle often, avoid the glow plug burnout causes listed above, and exercise caution while using your RC vehicle. Your glow plug being heated is normal and should not be a cause for alarm because it is the heat that it produces that starts the engine. But if your glow plug overheats it can have harmful effects on your nitro engine.

Also Read This: How do I know if my RC glow plugs are bad?

Can you use a burnt glow plug?

Straight answer, no. You never want to leave a burnt glow plug in your nitro engine. 

The sooner you replace it the better your RC vehicle will be and the faster it will run. Burnt-out glow plugs may make your vehicle struggle while starting. A burnt-out glow plug will not be able to ignite the fuel/air mixture. Your RC vehicle will also struggle to switch between high and low speeds if your glow plug is burnt out. 

Avoid using burnt-out glow plugs in your RC because although it might still work a bit, it will have terrible effects on your engine with time. 

How long does a nitro RC car glow plug last?

Sadly the lifespan of your glow plug cannot be accurately measured. 

To make your glow plug last longer you can tune your nitro engine properly; a nicely tuned engine makes your glow plug last a lot longer than a poorly tuned one.
If your engine is tuned well your glow plug can last for several months without needing a replacement. The lifespan of your glow plug is also determined by its quality; be sure to choose high-quality glow plugs that suit your engine’s nitro to avoid changing it often and wasting more money.


If your RC glow plug burns out way too often then you may need to have a professional take a look at your vehicle. Be sure to carry extra glow plugs with you so that if one burns out your day is not completely ruined. Tuning your car regularly is the best way to prevent glow plug burnouts so make RC tuning a part of your schedule.