Does a 5.9 Cummins Have Glow Plugs

Yes, a 5. 9 cummins diesel engine does have glow plugs.

Glow plugs in a diesel engine assist in the combustion process by heating up the air inside the combustion chamber during cold weather conditions. This is important because diesel engines rely on heat for ignition, which becomes more difficult in cold temperatures.

The 5. 9 cummins glow plugs are located in the cylinder head and are powered by the vehicle’s battery. They operate through an electronic control module that activates the plugs for a short period of time during engine start-up.

Despite the importance of this component, glow plugs are often overlooked during regular maintenance check-ups, but it is crucial to keep them in proper working condition for the engine to function smoothly.

Understanding Glow Plugs for Diesel Engines


What Are Glow Plugs And What Do They Do?

Glow plugs are electronic-heating devices that help diesel engines start. They’re fitted at the top of cylinders and preheat them. When you turn the key in a diesel engine, the glow plugs heat the cylinders, and the fuel ignites, starting the engine.

Glow plugs are essential for diesel engine ignition during cold weather. They need to warm quickly and sustain high temperatures to maintain proper combustion. Diesel engines without glow plugs can suffer from poor starting performance. To prevent this, diesel engines use glow plugs to increase ignition efficiency.

The heat generated by the glow plug vaporizes any diesel in the cylinder and ensures a smooth start. Without a glow plug in the 5. 9 cummins diesel engine, the engine may not start at all in winter temperatures.

Factors Affecting The Use Of Glow Plugs

Glow plugs are an essential part of diesel engines, including some versions of the 5. 9 cummins. The requirements of glow plugs differ depending on the type of diesel engine. Certain types require glow plugs to function properly, while others do not.

In cold weather conditions, glow plugs are required to assist in the starting process. The use of glow plugs can be impacted by weather conditions such as cold temperatures or moisture levels. It is crucial to utilize the correct type of glow plugs for the given engine.

Glow Plug Operation Training Module Trailer

Overview Of The 5.9 Cummins Engine

The 5. 9 cummins engine is one of the most popular diesel engines in the world. It’s widely used in pickup trucks, rvs, and heavy-duty vehicles. The engine has a displacement of 5. 9 liters and uses a high-pressure common rail fuel injection system.

It also has a turbocharger for better performance. Unlike most diesel engines, the 5. 9 cummins does not use glow plugs to start. Instead, it has an intake air heater which warms up the engine’s air before combustion. This helps the engine start reliably in cold weather.

The 5. 9 cummins is known for its durability and long lifespan, making it a favorite among diesel enthusiasts.

Finding Answers On Glow Plugs In 5.9 Cummins

Glow plugs are an integral part of diesel engines that aid in starting in cold weather. However, not all 5. 9 cummins engines have glow plugs. To check if a particular engine has glow plugs, you can look at the engine model number or consult the manufacturer’s manual.

Common issues with glow plugs in these engines include failure to heat up and pre-heating for too long, leading to carbon buildup. It is crucial to replace faulty glow plugs to prevent ignition issues and engine damage. Maintaining regular engine checks and replacing malfunctioning glow plugs can help ensure the engine’s longevity and reliable performance in cold weather.

Importance Of Glow Plugs’ Functionality In 5.9 Cummins

Glow plugs are crucial for a 5. 9 cummins engine to function properly. After ignition, these plugs heat up to aid in the combustion of diesel fuel, allowing the engine to start swiftly. If glow plugs begin to malfunction, engine performance will suffer, causing a decline in power and fuel efficiency.

This will significantly impair the vehicle’s overall performance, making it challenging to start during any climate. Delayed starting, poor mileage, and white or black exhaust smoke are all signs that the glow plugs in your engine are having problems. To avoid additional issues, it is recommended that you replace any defective glow plugs as soon as possible.

Maintenance Tips For 5.9 Cummins Glow Plugs

The 5. 9 cummins engine does have glow plugs. Glow plugs are essential in igniting the fuel inside the engine and they need to be maintained regularly. It is recommended to replace the glow plugs at least once every 100,000 miles.

Testing the glow plugs is relatively easy and can be done using a multimeter. When replacing the glow plugs, it is important to follow a few steps including disconnecting the batteries, removing the valve cover and using a torque wrench to tighten the new glow plugs.

By keeping up with regular maintenance and following proper replacement procedures, the glow plugs on your 5. 9 cummins engine can continue to ignite fuel efficiently and keep your engine running smoothly.


Having a 5. 9 cummins engine comes with its own set of questions for owners. One of the most commonly asked questions is whether the engine has glow plugs or not. However, after conducting research and going through various manuals and forums, we have come to the conclusion that the 5.

9 cummins engine does not have traditional glow plugs. Instead, it uses an intake manifold heater grid or grid heater to help with starting in cold weather conditions. This grid heater warms the intake air, making it easier for the engine to start even in extremely cold temperatures.

Understanding the functioning of the intake manifold heater grid and its relationship with the engine is crucial for maintaining a healthy and well-functioning vehicle. Always ensure that the heater grid is in good working condition to avoid any starting issues during the winter season.