Why Does Your Diesel Car Need AdBlue?

If you own or drive a diesel car built after September 2015, it probably requires AdBlue, also known as diesel exhaust fluid. But many are unaware of what AdBlue is, what is does, and why you need to keep your diesel engine topped up! If you’re a diesel vehicle owner but are unsure about AdBlue, check out these few frequently asked questions about AdBlue, its origins, and why your car needs it:

What Is AdBlue?

AdBlue, or diesel exhaust fluid, is a combination of urea and ionised water. Urea is the primary end-product of the metabolic breakdown of proteins in mammals, and is found prevalently in mammalian urine, blood, and sweat.

But worry not, no animals are involved in the production of synthetic urea for use in AdBlue! The synthetic urea is blended with deionised water at a ratio of 35% urea to 67.% water.

What Does AdBlue Do?

AdBlue is automatically sprayed into a diesel vehicle’s exhaust system. By injecting AdBlue in tiny amounts into the gas leaving the exhaust, the solution helps break down the nitrogen oxide in the exhaust fumes into separate nitrogen, oxygen, and carbon dioxide, which are far less harmful to the environment.

This process is known as Selective Catalytic Reduction (SCR), and has been in use in larger vehicles like busses and lorries for decades, so its effectivity has been proven over a long period of use.

Why Is AdBlue Required?

AdBlue became a legal requirement after a new set of vehicle exhaust emission regulations came into force in late 2015. These regulations are known as Euro 6, the sixth directive laid out by the EU intending to reduce harmful pollutants produced by vehicles. Since September 2015, all new diesel vehicles built had to be designed in line with Euro 6 regulations.

What Do You Need To Do?

AdBlue is usually topped up automatically at your engine service or MOT, but it’s best to check your engine’s AdBlue levels periodically in between services. Most vehicles that use AdBlue come with a dashboard gauge alongside your standard fuel gauge, allowing you to easily keep track of when you’re running low.