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  7. Exhaust Fluid System Fault F250: Top 2 Causes

Exhaust Fluid System Fault F250: Top 2 Causes

exhaust fluid system fault F250

Exhaust Fluid System Fault F250: Top 2 Causes

The Ford F-Series Super Duty Trucks are some of the most well-known Ford trucks around the world. These enormous workhorse trucks were designed as an expansion for the Ford F150 and started production in 1998. Since then, these trucks have gained massive popularity, but an exhaust fluid system fault F250 issue has often been a common complaint.

One of the main causes of the fluid system fault has often been related to contamination, and due to the sensitive nature of the fluid, contaminated particles could become an issue that clogs the pump and causes damage. Draining and replacing the fluid is often the main method to clean the pump and ensure the vehicle runs as it should.

Since the exhaust fluid system fault, the F250 version has become such a widespread issue, we believe that we should show you why it happens and how you can reset the exhaust fluid system fault that often accompanies some Ford Diesel Trucks. We will also look at the most common reasons for this issue occurring.

What Does The Diesel Exhaust Fluid (DEF) Do?

4x4 truck
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The main purpose of the DEF is to help vehicles reduce emissions. With emissions being one of the top causes of global warming according to scientists, Ford has designed the DEF to help reduce some of the emissions in Ford vehicles. Not only does it slightly reduce the carbon taxes on these Ford trucks, but makes them better for the environment.

The fluid from the exhaust will be sprayed into the exhaust system by the vehicle and the purpose is to be transformed into ammonia by the catalyst. The main reason for this is to have the ammonia transform harmful NOx emissions into nitrogen and water, which is released through the exhaust system and reduces overall emissions.

Two Main Causes Of The DEF Pump Failure

Before we can look at how to reset this pump failure, we need to look at why it happens. Expert mechanics have identified two main reasons that often lead to a DEF pump failure and could mess up the exhaust system of your Ford F-250.

1.      Hard Water Contamination

underneath of car
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Problem: Hard water is one thing that many people might not have heard about. However, hard water is water with high mineral content. The presence of hard water could lead to crystallization inside the pump, which leads to a mineral build-up. The mineral build-up will not only clog the filters, but it could cause the pump to be clogged.

Solution: The main method of cleaning hard water crystallization from your vehicle is to use a vinegar solution. The vinegar solution might not seem like something mechanical, but the acidity can help to dissolve some of the mineral crystallization. Alternatively, you can visit a mechanic and have them use a special mixture to clean the system, but this will cost you around $100 including labor.

2.      Diesel Making It Into The Pump

an engine
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Problem: While your vehicle might use diesel as the main power source, diesel should never be poured into the DEF pump. Since diesel is littered with different particles, it could cause some abrasion and the abrasion would significantly damage some of the components.

Solution: A petroleum-based solvent is often the best solution to clean the components. However, this method does not always work. It is recommended that you visit your mechanic or remove the components and manually clean them if possible. Unfortunately, this can be a tedious process, but it should not be more than $100.

2 Ways You Can Reset The Exhaust Fluid System On Ford Trucks

With this being such a common issue, many mechanics and experts have given us tips and tricks that enable you to reset the DEF in the comfort of your home. However, you still need to be careful and ensure that there is nothing seriously wrong with the DEF pump. Here are the three main methods to reset your DEF pump.

1.      Refill The Fluid

mechanic checking fluids
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By refilling the fluid, you will have some form of a stationary reset. However, this method is only useful when you determine that low fluid is the main cause of the issue. Once you have parked your truck and refilled the tank, you should be able to reset the DEF manually. It should also reset automatically by driving at a slow speed after having the truck idle for a while.

2.      ECU Manual Reset

battery inside car
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In many modern vehicles, the ECU is one of the most important components and you will heavily rely on the ECU to let you know of any potential issues within the truck. When it comes to “hard resetting the ECU”, you will need to be mechanically skilled. You can open the hood and loosen the lock nut that connects to the battery.

Once the terminal is disconnected, you can leave the vehicle for about half an hour, allowing the ECU to drain. Once the battery is drained, the ECU should automatically reset.


Can I Drive With The DEF Light On?

While it is possible to drive your vehicle with the DEF light flashing, experts don’t recommend it. Not only can the continuous abrasion cause even more damage to the vehicle, but the ECU will often limit the speed of the vehicle to 5 MPH. Once you have parked your vehicle, it could take up to 1-hour for everything to reset once you have filled the DEF.

Can I Bypass The DEF System?

If you are dealing with a constant DEF light flashing, you might have some thoughts of bypassing the system. While it is possible, you need to understand that it could lead to a massive fine if you are pulled over and the issue is detected. Additionally, it could affect the warranty of your vehicle and you might even lose the warranty. It might even cause significant engine problems commonly seen in the Ranger.

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