Unnaturally colored exhaust smoke can cause concern even the most composed vehicle owner.…
What is AdBlue and how does it work?
The development of the automotive industry has resulted not only in increased performance of cars, but also in concern for the environment. Over the years, along with new engines, new methods have been implemented to reduce exhaust emissions or make their composition less harmful. This is where catalytic converters, exhaust gas recirculation systems, particulate filters, modern computer-controlled fuel supply systems and economizers come from. Finally, AdBlue, an agent that neutralizes exhaust gases from diesel engines, was created.
- AdBlue is an agent that neutralizes exhaust gases from diesel engines.
- AdBlue has been in all diesel cars since 2015.
- Lack of AdBlue will not damage the car, but it will limit its use. At the beginning, the car will operate at limited engine speeds.
- Did you fill up with the wrong fuel? Check how to drain fuel from the tank!
- What is AdBlue?
- What is AdBlue for?
- How does AdBlue work?
- Where to pour AdBlue?
- Where to buy AdBlue?
- What cars use AdBlue?
- What can happen when you run out of AdBlue?
- Can AdBlue be replaced with anything?
- Can AdBlue freeze?
What is AdBlue?
Let's start from the beginning, what exactly is AdBlue? AdBlue is an agent that neutralizes exhaust gases from diesel engines. In fact, it's actually a trade name. In fact, the composition of this substance is a 32% aqueous solution of urea. Urea itself is a popular fertilizer. It is non-flammable, accelerates corrosion to some extent, and is also safe for living creatures.
What is AdBlue for?
You might ask why such a substance is needed in a car at all? It's all because of emission standards exhaust. AdBlue breaks down harmful nitrogen oxides into ammonia and CO2. The first installations reducing nitrogen oxide emissions appeared in the first decade of this century in trucks powered by diesel engines. Implementation of subsequent EURO exhaust emission standards resulted in the mandatory installation of the AdBlue system in new vehicles.
In 2015, the European Union presented new EURO-6 standards and obliged all manufacturers of diesel vehicles to reduce emissions of harmful nitrogen oxides. Since then, the AdBlue system (or similar solutions) have been installed in new diesel-powered vehicles. Of course, if the manufacturer meets the requirements of the standard without using it, then its installation is not necessary, but such cases are few.
How does AdBlue work?
It all comes down to the above-mentioned nitrogen oxides (NOx), which are highly harmful to the natural environment. To neutralize them, it is necessary to inject urea under high pressure into the exhaust system. Water evaporates from the AdBlue solution due to high temperature. Urea decomposes into ammonia. In the catalytic converter, it then reacts with nitrogen oxides to produce water and nitrogen, which are no longer harmful.
For the system to work, it requires a separate tank, a pump and a controller, as well as a number of sensors.
Where to pour AdBlue?
The Adblue filler is usually located under the fuel flap. Right next to the diesel filler neck. In the case of older vehicles, however, it may turn out that you have to look for it in other places - for example under the hood, on the side of the trunk or even in the spare wheel well. Why so? This is due to the fact that in some models the SCR system, which is responsible for the breakdown into ammonia and CO2, was not installed at the design stage. Hence
Where to buy AdBlue?
It is now clear what AdBlue is, how it works and why it is used. The next question is where can you buy it? AdBlue can be refilled at gas stations, but you can also buy it in self-filling cans.
What cars use AdBlue?
This system is actually necessary in cars powered by diesel fuel. This is because their engines need a lot of oxygen to function properly, and controlling its dose is not possible, or the technology required for this is not economically justified. Excess oxygen, as a result of combustion processes, combines with nitrogen and creates the already mentioned nitrogen oxides. In gasoline engines, it is easier to control the fuel to air ratio, and the trace amounts of nitrogen oxides remaining from the engine's operation are captured by the catalytic converter.
In effect, a system AdBlue can be found in almost all diesel cars manufactured after 2015.
What can happen when you run out of AdBlue?
AdBlue consumption ranges from 2-6% of diesel fuel consumption, so one tank is enough for a really long time. Unfortunately, in some cars, refueling the fluid is problematic, e.g. it requires dismantling the trunk carpet. However, if for some reason you forget to refill the urea solution, remember:
- If you are refilling the liquid from a can and not from a dispenser, it is best to use the entire contents of the container at once. This is because AdBlue in a canister tends to crystallize quickly and then loses its properties.
- Also remember to Clean spilled AdBlue immediately with water - contact with metal causes corrosion!
- Never do not mix AdBlue with fuel, pour the agent only into a dedicated tank! It will have a blue cap, labeled AdBlue or DEF.
- Refill AdBlue only with the engine turned off. It is best to wait 2-3 minutes after immobilization.
Running out of AdBlue in the tank will not cause any damage, but it will certainly limit the use of the car. The EORO 6 standard assumes how much nitrogen oxides a vehicle can emit into the atmosphere, so After AdBlue runs out, the car will initially run at limited performance – all to reduce exhaust emissions until the fluid is refilled. Ultimately the car will turn off and you won't be able to start it until the urea solution is replenished in the tank.
Can AdBlue be replaced with anything?
AdBlue is the trade name of the product, so it can be replaced with substances from other manufacturers, but with the same composition. However, there is no other alternative to the urea solution – pouring anything else into the AdBlue system will cause a failure. If detected at a diagnostic station or during a roadside inspection, the AdBlue emulator may result in the confiscation of the vehicle's registration certificate.
Can AdBlue freeze?
AdBlue freezes at approximately -11°C in winter, so in Poland this can happen quite often. This is problematic because, as a result of crystallization, urea particles may clog the pipes, pump and filter in the system and settle in the exhaust pipe and its components. To avoid problems, in winter it is better not to fill the AdBlue tank up to the cap, so that the freezing substance has room to expand. Optimally fill the system to approximately 3/4 of its capacity.
After the frosts stop, the urea solution will become liquid again, but its properties are especially important concentration, will be different, which will limit the effectiveness of the system.
AdBlue helps reduce the amount of harmful substances emitted by diesel cars. Even though its lack will not cause damage, it is worth remembering to replenish it. Especially since the car may turn off. For more information, please see our other articles.
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