Schwarz Motor Repairs

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Avoiding Costly Mistakes: AdBlue vs. Diesel

At Schwarz Motor Repairs, we've seen an increasing number of cases where AdBlue is mistakenly added to diesel vehicles’ fuel tanks. This mix-up can lead to significant damage and costly repairs, so it's important to understand the consequences and how to address them.

What Happens When AdBlue Is Added to the Fuel Tank?

AdBlue is a fluid used to reduce harmful emissions in diesel engines, specifically for vehicles equipped with Selective Catalytic Reduction (SCR) systems. It is not a fuel and should never be added to the fuel tank. Unfortunately, accidents can happen, especially since AdBlue is typically dispensed from a nozzle similar to fuel pumps.

If AdBlue is introduced into the diesel tank, it can cause severe problems because it doesn’t mix with diesel. Instead, it creates a sticky, sludgy substance that can clog your vehicle's fuel system. From the fuel pump to the injectors, the entire system may be compromised.

Potential Damage to Your Vehicle

Here are some of the ways your vehicle could be affected:

Fuel System Contamination: AdBlue crystallizes when exposed to diesel fuel, which can block filters, fuel lines, and injectors.
Engine Damage: Trying to start or run the engine after mis-fueling can circulate the contaminated mixture, increasing the likelihood of engine damage.
Corrosion: AdBlue is corrosive to certain materials, potentially damaging metal components within the fuel system.

Ignoring the issue or attempting to drive the car in this condition can lead to even more extensive damage, potentially requiring a full replacement of the fuel system or engine components.

What to Do If You Misfuel with AdBlue

If you realise that AdBlue has been added to your diesel tank, the most important thing is to not start the engine. Starting the vehicle can circulate the contaminated fuel, making the issue worse. Instead, follow these steps:

Call for Professional Assistance: Contact a trusted mechanic or breakdown service to have your vehicle towed to a repair facility. Schwarz Auto is always ready to help in these situations.
Drain the Fuel Tank: The contaminated mixture must be safely removed. This involves draining the entire fuel tank to eliminate all traces of AdBlue and diesel.
Inspect and Clean the Fuel System: Depending on how far the AdBlue traveled, components like the fuel pump, filters, and injectors may need cleaning, repair, or replacement.
Replace Damaged Parts: If corrosion or extensive contamination has occurred, replacing affected parts of the fuel system may be necessary.

How to Avoid This Mistake

Prevention is always better than repair. To avoid this mix-up, be sure to double-check the label on the pump before filling your tank. Most diesel vehicles have a clearly marked, smaller filler cap for AdBlue, separate from the fuel cap. Familiarising yourself with your vehicle’s layout and refueling requirements can help you avoid costly errors.

Accidentally adding AdBlue to your diesel fuel tank can lead to serious problems, but acting quickly and seeking professional help can minimise the damage. At Schwarz Motor Repairs, we’ve helped many customers recover from this mistake, and we’re here to assist if it happens to you. Remember, prevention starts with being aware and attentive when refueling your vehicle.