• 03/04/2025
  • 3min

How to protect the exhaust system of modern series diesel engines

#Car

What is AdBlue®? What is it needed for? What do you have to bear in mind when using it? We explain what you need to know about AdBlue® and how to prevent expensive repairs.

 

Newer-generation diesel vehicles require urea in addition to fuel. If this is dissolved in demineralized water, an additive is produced, which is sold under the name AdBlue®. This reducing agent is essential for compliance with European standards for nitrogen oxide emissions, but can also lead to serious damage to the exhaust system in the event of insufficient evaporation.

How AdBlue® works in the exhaust system

The liquid urea solution AdBlue®, also known as diesel exhaust fluid (DEF), is dosed in diesel vehicles with exhaust gas treatment systems (SCR systems) via a separate tank and injected into the hot exhaust tract. There, the pollutants produced by the combustion process mix with the reducing agent and react to form harmless water vapor and nitrogen, whereupon they comply with the standardized nitrogen oxide values and are emitted via the tailpipe.  

Easy to use

Add 0.25 percent to the AdBlue® solution (1:400). 25 ml is sufficient for 10 l AdBlue®. 250 ml is sufficient for 100 l AdBlue®. 2.5 l are sufficient for 1000 l AdBlue®. The product is suitable for continuous use. Do not add to the fuel! When adding to the AdBlue® tank, it should ideally be added after the filling process, as slight foaming may occur.

Close-up of the inlet valves (left: before cleaning, right: after cleaning)

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