- 03/04/2025
- 3min
How to protect the exhaust system of modern series diesel engines

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.
