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Signs Your DEF Filter Needs to Be Changed

If you've ever driven a diesel truck or car, you know how powerful and efficient these vehicles can be. Unfortunately, this strength comes at a cost because it's difficult to maintain the DEF filter in diesel cars.

If your DEF filter isn't working correctly, several warning signs indicate you need to replace it as soon as possible. Read on to know more!

What is DEF

DEF is a urea-based solution that reduces NOx emissions from diesel engines. It is added to the fuel tank of diesel engines, made up of 32.5% urea, 66.5% deionized water, and 1% antifreeze to prevent freezing at a sub-freezing temperature (which is between 30-40 degrees Fahrenheit).

DEF is a crucial component in keeping your vehicle operational, just like any other type of engine fluid. Before the exhaust comes out of the tailpipe, a water-urea mixture is injected into it to cause a chemical reaction. This reaction converts harmful pollutants into clean air and keeps them from entering the atmosphere.

What is DEF Filter

A DEF filter is a system that cleans the diesel exhaust fluid to its full capacity, also known as diesel exhaust fluid (DEF) before it enters the vehicle's fuel system.

Although the precise location of the DEF filter may vary depending on the kind of vehicle, it will almost always be found inside the tank or container that is used to store the fluid.

Your vehicle's emissions control system includes the usage of DEF as a component. It is a fluid that is mixed in with the fuel that is stored in the tank of your car. Your engine can continue to operate in a clean and efficient manner without being harmful to the environment if you use DEF.

It is an important component of the gasoline delivery system of your vehicle. It contributes to ensuring that you get the most out of your fuel and that there are no pollutants present in the system.

Signs Your DEF Filter Needs to Be Changed

If you notice one or more of the following signs, it's time to change your DEF filter:

Check Engine Light Comes On

It's possible that the check engine light may turn on in your vehicle. It is typical to take note of this as soon as possible since it is a warning light and it signifies that something needs to be corrected.

There are a variety of issues that might trigger the DPF warning light, one of which is an issue with the DEF filter. The diesel exhaust fluid (DEF) filter is located between the diesel tank and the diesel pump, and it removes any contaminants from a clogged DPF filter that may otherwise cause failure or damage to components further down the line (like injectors).

When you drive through locations that have a high concentration of dust or other airborne pollutants, like construction zones, those toxins will make their way into the cabin of the car through the ventilation system. Because of this, having clean air filters, monitoring the engine control module (ECM) and its fault codes regularly are quite necessary for the purpose of safeguarding your health while you are driving.

Poor Fuel Efficiency

It is very necessary to get your DEF filter replaced at the recommended intervals. The DEF filter is a component of the system that plays a role in reducing the risk of causing harm to the engine. It also helps guarantee that you completely clean your diesel particulate filter, which may also be referred to as a DPF filter. This will help to extend the life of the filter by encouraging passive regeneration and maintaining good operating order.

It is possible that a clogged DEF filter is the cause of your vehicle's bad handling as well as its low efficiency in terms of fuel consumption. This may occur if you travel through dusty conditions or if you don't get your diesel fuel tank refilled frequently enough, extensively hurting the passive DPF regeneration of your engine. If this happens to your DPF filters, getting the assistance of an experienced professional may help you decide whether or not you should replace your DEF filter right away.

Decrease in Engine Performance

You may be surprised that diesel exhaust fluid is just a fuel type. It's added to the vehicle's fuel tank and helps reduce the harmful emissions from diesel engines.

DEF is colorless and odorless, so you won't know it's even there unless you add too much and get a message on your dashboard telling you to refill the tank. That's because DEF is stored in a separate tank in your vehicle.

Suppose engine performance suddenly decreases and your vehicle shows signs of needing new injectors or other repairs. In that case, this could indicate that it's time to change your DEF sensor filter and oil - both recommended every 10k miles by most manufacturers. If they haven't been changed recently (or ever), they might not be working correctly now either!

Trouble Starting

The DEF tank is a storage unit for the DEF mixture. It holds about 3 gallons at a time, and the vehicle uses this liquid to reduce nitrogen oxide emissions.

When you start your car, the fuel system pressurizes the tank with outside air to create enough pressure inside for injection into the exhaust stream.

When you drive away without a full tank, you'll notice that starting will be more difficult than usual because there isn't enough fuel in front of the injectors to start combustion immediately; opening your throttle will result in stalling until everything catches up.

Strange Smells

Strange smells can signify that your DEF filter needs to be changed.

You may notice a somewhat unfamiliar smell coming from the DEF tank, or you may just catch a strange smell in the cab of your truck. In either case, it's probably time to change your blocked DPF filter.

If you notice a strange smell coming from the DEF tank, there are two possible reasons. It’s either you need to replace your filter or an issue with the tank itself. If you think it's an issue with the tank, you should check for any leaks or cracks in its exterior soot before replacing your filter to prevent permanent damage.

Also, If you're experiencing a strange-smelling cab, there may be something wrong with your cab air vents or cabin air filters. It could also be due to dust buildup in these areas, so try to implement a regular, thorough cleaning process, and replace any cabin air filters as necessary for active regeneration.

Turbocharger Damage

If you suspect your DEF filter needs to be changed, it’s essential to check for signs of damage. The most common symptom is damage to the turbocharger.

If your engine has been experiencing problems with overheating, failing, or losing power, or If it makes any other unusual noises, this is an indication of turbocharger failure. This can also cause damage to other parts of your car as well as reduce its lifespan.

Shop Filters at Heavy Duty Pros

We hope you now have a better understanding of how to determine if your DEF filter needs to be replaced. Remember that the signs listed above are not all-inclusive, and there could be other issues that need to be addressed before your DEF filter needs replacing.

Don't let the hassle of finding a replacement DEF filter keep you from doing your job. Heavy Duty Pros is the perfect place to go if you're looking for quality filters at great prices.

We offer a wide selection of filters that are sure to be compatible with your truck's make and model and excellent customer service. Click here to browse our wide collection of high-quality, industry-standard diesel engine filters , or call us for further assistance!