What is AdBlue and do you need it?

Adblue reduces the environmental impact of your diesel vehicle

AdBlue, also known as Diesel Exhaust Fluid, is actually a colourless liquid that is composed of 67.5% distilled water and 32.5% high grade chemically produced carbamide solution. Contrary to popular belief, it’s not made of animal urine, it just has some of the same chemical components.

AdBlue works in conjunction with a treatment system known as Selective Catalytic Reduction (SCR) and is used by a growing number of car makers to meet the increasingly stringent environmental regulations.

In a nutshell, AdBlue turns harmful emissions into far less harmful emissions.

Does my car need AdBlue?

AdBlue is injected into the exhaust system just ahead of the catalytic converter to help reduce the harmful exhaust emissions, nitrogen oxide and nitrogen dioxide (NOx).

If you have a new Euro 6 diesel car (the tightest level of NOx limits), registered after September 2015, the likelihood is that it uses AdBlue technology. These emissions not only pollute the air, causing smog and acid rain, but can also cause respiratory and breathing problems in vulnerable people.

There are many ways to know if your car uses AdBlue and it would be advisable to find out well before the warning light comes up on the dash. This is because most diesel drivers will need to top up their AdBlue at least once between services, particularly if you’re a high mileage motorist. What a lot of people don’t realise is that when you run out of AdBlue the vehicle will not simply belch out more harmful gases, it will either lose power and revert to ‘limp home’ mode or it simply won’t start.

Sometimes there is a clue in the vehicle model name which may have ‘blue’ or ‘SCR’ in it. AdBlue is stored in its own separate tank so you could look for the blue filler cap which is normally located either next to your fuel filler cap, in the boot or under the bonnet. If in doubt you can always check your vehicle manual or ask your local garage for advice.

Dos and Don’ts of using AdBlue

As with all new technology there is a learning curve and although the process may seem simple it’s best not to get complacent. No one ever thinks that they will put diesel in a petrol car or vice versa but it can happen – so here are some simple do’s and don’ts when it comes to topping up AdBlue.