What to Do if Put AdBlue in Diesel Tank by Mistake

Putting the wrong fluid into your vehicle’s fuel tank can cause serious damage and costly repairs. One common mistake diesel vehicle owners make is accidentally filling the diesel tank with AdBlue. This error can be alarming, but knowing what to do immediately can save your engine and wallet. This post explains the risks, the steps to take if this happens, and how to avoid it in the future.

Diesel fuel tank with nozzle inserted

What Is AdBlue and Why It Should Never Go in the Diesel Tank

AdBlue is a liquid solution made of urea and deionized water. It is used in diesel vehicles equipped with Selective Catalytic Reduction (SCR) systems to reduce harmful nitrogen oxide emissions. AdBlue is stored in a separate tank and injected into the exhaust system, not the fuel tank.

Putting AdBlue into the diesel tank causes several problems:

• Chemical incompatibility: AdBlue is not a fuel and does not combust. It can damage fuel system components.

• Corrosion risk: The urea solution can corrode metal parts inside the fuel tank and fuel lines.

• Engine damage: The engine may stall or fail to start because the fuel system is contaminated.

• Costly repairs: Cleaning or replacing the fuel tank, fuel pump, and injectors can be expensive.

  
  

Understanding these risks highlights why immediate action is necessary if you realize the mistake.

How to Recognize You Put AdBlue in the Diesel Tank

Sometimes, the error is obvious, but other times it can be confusing. Here are signs that AdBlue may have been put into the diesel tank:

• The fuel nozzle did not fit properly but was forced in.

• The vehicle fails to start or stalls shortly after refueling.

• Warning lights related to the fuel system or engine appear on the dashboard.

• A strong chemical smell near the fuel tank or exhaust.

• The fuel cap or filler neck looks unusual or has a blue tint (AdBlue is often blue).

  
  

If you suspect this mistake, do not start or drive the vehicle.

Immediate Steps to Take if You Put AdBlue in the Diesel Tank

If you realize you have put AdBlue in the diesel tank, follow these steps:

1. Do not start the engine

   Starting the engine will circulate the contaminated fluid through the fuel system, increasing damage.

   
   

2. Call a professional emergency service

   Contact a wrong fuel emergency specialist immediately. For example, you can call 07771 029122 for expert assistance. They can provide advice and arrange for safe vehicle recovery.

   
   

3. Inform the recovery team about the mistake

   Clearly explain that AdBlue was put in the diesel tank. This helps them prepare the right equipment and cleaning methods.

   
   

4. Do not attempt to drain or fix the problem yourself

   Fuel systems are complex and require professional tools and knowledge to clean safely.

   
   

What Professionals Do to Fix the Problem

When your vehicle reaches a garage or specialist, they will:

• Drain the entire fuel tank completely.

• Flush the fuel lines, fuel pump, and injectors to remove all traces of AdBlue.

• Inspect the fuel system for corrosion or damage.

• Refill the tank with clean diesel fuel.

• Test the engine to ensure it runs smoothly.

  
  

This process can take several hours and may be costly depending on the extent of contamination and damage.

How to Prevent Putting AdBlue in the Diesel Tank

Prevention is the best way to avoid this costly mistake. Here are some practical tips:

• Know your vehicle’s tanks: Familiarize yourself with the location and appearance of the diesel and AdBlue filler caps.

• Look for color codes: AdBlue filler caps are usually blue, while diesel caps are black or green.

• Read labels carefully: Most vehicles have clear labels near the filler necks.

• Use different nozzles: AdBlue nozzles are designed to be smaller and should not fit into diesel tanks.

• Ask for help: If you are unsure, ask the fuel station attendant for assistance.

• Stay focused: Avoid distractions when refueling, especially if you are in a hurry.

  
  

What to Do if You Are at a Fuel Station and Realize the Mistake

If you notice the error while still at the fuel station:

• Stop immediately and do not start the engine.

• Inform the station staff about the mistake.

• Call a wrong fuel emergency service like 07771 029122 for advice.

• Arrange for professional help to drain the tank before driving.

  
  

How Much Does It Cost to Fix AdBlue in Diesel Tank Mistakes?

The cost varies depending on the vehicle and damage extent. Typical expenses include:

• Fuel tank drainage and cleaning: £150–£300

• Fuel system flush and injector cleaning: £200–£500

• Replacement of damaged parts (fuel pump, injectors): £500–£1500 or more

  
  

Acting quickly reduces the risk of severe damage and higher costs.

Final Advice for Diesel Vehicle Owners

Mistakes happen, but knowing what to do can prevent disaster. If you accidentally put AdBlue in your diesel tank:

• Do not start the engine.

• Call a wrong fuel emergency specialist immediately (e.g., 07771 029122).

• Arrange professional draining and cleaning.

• Learn how to avoid this mistake in the future.

  
  

Taking these steps protects your vehicle and saves money. Keep emergency numbers handy and stay calm if this happens.