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What Is AdBlue?

what is the point in AdBlue

AdBlue is the latest emission reducing chemical used in diesel cars. It comes in the form of a non toxic liquid that is colorless in appearance and made through a combination of water and urea.

Car manufacturers are under extreme pressure to reduce harmful emissions and AdBlue is the latest savior. Production of new diesel engines will eventually become extinct in around 50 years but for now, AdBlue is whats needed.

The emission scandal has kick started the need to find technology to reduce emissions. Lets not forget the Volkswagen Emission Scandal that hurt their reputation significantly and of course sales of new diesel cars.

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How Does AdBlue Work?

For cars that use it, in short the liquid is injected to the cars exhaust gases to emit a less harmful gas. The gas it produces is a combination of nitrogen and oxygen that is harmless to the environment. The harmful gas from cars that do not use AdBlue is momo-nitrogen.

It has been tested in lorries, buses and heavy load trucks for a long time and now the technology has been passed downed to cars.

How Much AdBlue Is Needed

The obvious questions from many motorists is the amount required to keep to the guidelines. The calculation figured out by experts is approximately 5% of your diesel tank i.e. 1 liter of AdBlue for every 20 litres of diesel.

AdBlue can be added to your car through the forecourt, which you have probably seen grown in popularity. However, you can also buy AdBlue online to save that trip and add is as and when your car requires it at home.

How Do You Add AdBlue To Your Car

Topping up the amount you have in your car is a simply as filling your car with fuel. The filler cap is usually clearly labelled with “AdBlue” and you simply place the nozzle into the slot and fill it up. However, the tank for AdBlue is not always where the fuel filler cap is. For example on some Mercedes vehicles you will find the filling cap in the boot.

Always check your cars handbook to advise on the amount you should fill up and when you should.

adblue filler cap in boot

Driving With No AdBlue

You may find yourself running low on AdBlue, however most vehicles will give you clear indication of when it needs to be topped up. Some cars will not even start if you have not filled it up with AdBlue. The liquid can be stored or kept in the fuel tank for at least a year, so always try and top it up when possible.

When it comes to commercial vehicles that drive thousands of miles each year, there are fines for not having enough AdBlue in the car. However, to avoid fines, there are some people who use a small module to trick the readings into thinking there is surplus in the vehicle.

Being caught with one of these small ECU’s in the vehicle will land yourself into larger fines, we advise that you do not use one of these.

Is AdBlue A Waste Of Time

AdBlue is a fuel additive such as your standard fuel additive for diesel cars. Its main purpose is to reduce the NOX levels in the exhaust gases that your vehicle emits. The technology itself is called SCR (Selective Catalytic Reduction) and in my eyes, it makes perfect sense.

To avoid the early death of diesels cars and keep them on the road for that much longer, emissions have had to drop. AdBlue and SCR technology has increased the life of the diesel production line and its now in most new diesel cars.

Regardless of your thoughts on diesel cars, they provide the best fuel economy compared to alternative fuels and used in all scenarios i.e. agricultural, lorries etc.

procarreviews author

Written By Dan

About the Author

Dan is an automotive journalist and owner of over 10 cars ranging from supercars, tuned cars, classics and your good old beater cars. He always likes to get his hands dirty with nut and bolt restorations or detailing sessions using the best products on the market.

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