What is AdBlue and Why is it Important?

15th Jul 2019



Recently, we were sat in the office watching cat videos on YouTube when one of our colleagues, called Kenny, turned to us and told the tale of a woman who filled her car's fuel tank purely with AdBlue. And as a result of said tank being filled with AdBlue, the car didn't feel very well afterwards (slight understatement).

Naturally, because we're deeply sympathetic people, we didn't laugh hysterically at this person's lack of judgement. Although we were astonished to hear of someone doing this to what we gather was an expensive motor, we actually learned that this was quite a widespread issue across the country; although the majority of other examples aren't this extreme.

Being the lovely company that we are, we thought we would answer all the common questions surrounding AdBlue.


What is AdBlue?

AdBlue is a biodegradable, completely harmless solution designed to help diesel vehicles meet the latest Euro exhaust emissions regulations.

AdBlue is made from 32.5% urea and 67.5% deionized water. And no, it's not actual urine, it's made from synthetic materials.

How does AdBlue work?

Typically, modern diesels utilise a treatment system called Selective Catalytic Reduction (SCR to you and us). Essentially, the SCR blends the AdBlue with the engine's exhaust gasses, which creates a chemical reaction, to convert nitrogen oxides (NOx) into nitrogen, water and carbon dioxide (CO2). As a result, the gasses emitted are less harmful to the environment and our health.

Does my car have an SCR system?

The SCR system is typically found on diesel powered vehicles that have been designed to meet Euro 6 regulations. Euro 6 was introduced in 2014, so any diesel vehicle built after that should, in theory, utilise AdBlue. Typically, the more recent the diesel powered car, the more likely it is to use an SCR system.

If you're in any doubt, then consult with your vehicle's handbook.

What happens if I don't fill up my car's AdBlue tank?

SCR equipped cars typically reduce engine performance, with some not starting at all if AdBlue levels are completely depleted. Don't worry about it though, because a low-level warning light will appear on your vehicle's dashboard long before you run out.

Where do I find AdBlue?

A wide variety of fueling stations will have AdBlue in abundance, whether it's as a standalone pump, or as large containers you can take home. Alternatively, you can find AdBlue being sold at local car dealerships, supermarkets, and online.

How much is AdBlue?

Prices vary greatly across locations and sellers, but a few searches around local and national sellers suggest that £1 per litre is around the going rate. Evans Halshaw Peugeot, for example, offer a flat rate of 10 litres for £9.99, which is very good.
Peugeot 308 GT

On top of fuel, that's going to sting me financially, isn't it?

Not as much as you'd think. Consumption is completely dependent on the vehicle, your driving style, and the journey. However, it could be anywhere from 3,000 to 12,000 miles between refills. It's not uncommon to have to refill your tank at least once between dealer services.

How do I refill the tank?

Similar to refilling your diesel tank, there will be an AdBlue filler cap somewhere on your car. Where the filler nozzle is completely varies from car to car, so we would recommend checking your vehicle's handbook.
If you have any doubts regarding AdBlue and its use in your car, please don't hesitate to contact your nearest Evans Halshaw retailer, who will have knowledgeable team members on standby ready to assist you with any queries.

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