Everything you need to know about AdBlue: what is it and what is it for?

AdBlue has become an indispensable element in the latest diesel vehicles. With increasingly stringent environmental standards, this liquid plays a key role in reducing polluting emissions. Since 2015, with the entry into force of the Euro 6 standard, many manufacturers have equipped their models with systems that require AdBlue, as a way of complying with nitrogen oxide (NOx) emission limits.

What is AdBlue?

AdBlue is a solution made up of 32.5% high purity urea and 67.5% demineralised water. Despite its technical name, it is a safe substance, odourless and non-toxic. It's important to note that AdBlue is not mixed with fuel: it has its own tank and is injected directly into the vehicle's exhaust system.

AdBlue's composition and function

The function of AdBlue is to enable Selective Catalytic Reduction (SCR), a chemical process that transforms the nitrogen oxides present in exhaust gases into nitrogen and water vapour - two elements that are harmless to the environment. This process takes place inside the catalytic converter and is essential for reducing emissions in modern diesel engines.

What is AdBlue used for?

AdBlue is used to significantly reduce the emissions of polluting gases produced by diesel vehicles. When used in the SCR system, AdBlue helps cars comply with stringent environmental standards and reduce the environmental impact of daily driving, especially in urban areas with a higher concentration of traffic.

Reducing emissions and protecting the environment

The use of AdBlue contributes to a reduction of up to 90 per cent in nitrogen oxide emissions, one of the main causes of air pollution and respiratory problems. By reducing these harmful gases, AdBlue helps to protect the environment and promote more sustainable mobility.

Who uses AdBlue?

Most light and heavy-duty vehicles with a diesel engine manufactured from 2015 onwards use AdBlue. This includes passenger cars, commercial vans, lorries, buses and even agricultural and industrial machinery. The use of AdBlue is now standard for most modern diesel vehicles.

How to top up AdBlue

Topping up AdBlue is a simple process, but it must be done carefully. The liquid should only be poured into the tank designated for the purpose, using appropriate packaging or specific pumps. Avoid direct contact with the skin and clean up any spillages immediately.

Where to deposit AdBlue and how to fill up safely

The location of the tank varies depending on the vehicle model. It can be near the fuel filler, in the boot or in the engine compartment. Refuelling should be done with the engine switched off, on level ground and with the aid of a funnel or anti-splash system.

When to top up AdBlue

How long AdBlue lasts depends on your driving style, consumption and the size of the tank. On average, it lasts between 5,000 and 15,000 kilometres. The vehicle alerts you in advance when you need to refuel, usually with more than 2,000 km of range remaining.

Warning signs on the dashboard

Alerts on the dashboard indicate when the AdBlue level is low. If ignored, the system can limit the vehicle's performance or, in more serious cases, prevent it from starting until the fluid is replenished. Always refuel before reaching the minimum level.

What happens if I run out of AdBlue?

If the AdBlue tank is completely empty, the emission control system deactivates. As a result, many vehicles prevent the engine from starting until it has been refuelled. There is no immediate risk to the engine, but the immobilisation can cause inconvenience.

AdBlue's impact on the engine

AdBlue does not interfere directly with engine operation. It only acts on the exhaust gases, so it doesn't affect performance or consumption. However, it is essential for the SCR system to work properly and for the vehicle to comply with environmental regulations.

Myths about AdBlue

It is false that AdBlue reduces the car's power. Another common myth is that it can be replaced with water or other liquids - this can damage the system and void the manufacturer's warranty. Always use certified and suitable products!

Care of AdBlue

Store AdBlue in a cool, dry place away from direct sunlight. The average shelf life is around 12 months after opening. Avoid using reused or poorly sealed containers, as contamination can compromise the SCR system.

Storage, shelf life and mistakes to avoid

Never mix AdBlue with fuel, water or other liquids. Only use products certified to ISO 22241. Always check the expiry date on the packaging before use.

Price and where to buy AdBlue

AdBlue costs between €0.60 and €1.00 per litre, depending on the format and place of sale. It is available at petrol stations, car centres, supermarkets and online shops. For those who drive many kilometres, buying larger packs can pay off.

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AdBlue is more than just a liquid, it's a silent ally that protects the environment and ensures that your diesel car complies with legal regulations. Keeping your AdBlue levels up to date is a simple gesture that makes a huge difference to the health of your engine, the planet and all of us.

Translated with DeepL.com