SCR System Cleaning: How It Works and Why It’s Necessary

Black SUV and grey AUV crossing a pedestrian line during daytime.

Amidst the complexities of diesel engine maintenance, Selective Catalytic Reduction (SCR) system cleaning stands as a critical yet often overlooked aspect.

This guide discusses the nuances of SCR system cleaning, explaining its significance in maintaining optimal engine performance and meeting emissions standards.

From exploring the underlying mechanisms to outlining the necessity of regular maintenance, we provide comprehensive insights tailored to diesel vehicle owners and fleet managers.

By understanding the intricacies of SCR system cleaning and its essential role in emissions control, readers will gain valuable knowledge to ensure the longevity and efficiency of their diesel engines.

SCR System Cleaning: What Is It?

Selective Catalytic Reduction (SCR) system cleaning is a maintenance procedure designed to ensure the optimal performance and longevity of the SCR system in diesel engines.

The SCR system is responsible for reducing harmful nitrogen oxide (NOx) emissions by converting them into nitrogen (N2) and water vapor (H2O) through a catalytic reaction with a urea-based solution known as diesel exhaust fluid (DEF) or AdBlue.

Over time, the SCR system can become contaminated with deposits and residues from the exhaust gases, which can impair its efficiency and effectiveness in reducing NOx emissions. SCR system cleaning involves removing these deposits and residues through various methods, such as flushing the system with cleaning agents or physically cleaning the SCR catalyst.

By regularly cleaning the SCR system, diesel vehicle owners can ensure compliance with emissions regulations, maintain optimal engine performance, and prolong the lifespan of the SCR components.

How SCR System Cleaning Works?

SCR system cleaning typically involves several steps to remove deposits and residues that accumulate in the Selective Catalytic Reduction (SCR) system of diesel engines:

  • Inspection:The SCR system is visually inspected to assess the level of contamination and identify any potential issues.
  • Flushing:Flushing the SCR system with a specialized cleaning solution helps dissolve and remove deposits from the SCR catalyst and other components.
  • Cleaning Agents:Cleaning agents may be introduced into the SCR system to break down stubborn deposits and residues, facilitating their removal.
  • Physical Cleaning:In some cases, physical cleaning methods such as brushing or scraping may be used to remove hardened deposits from the SCR catalyst surface.
  • Rinsing:After cleaning, the SCR system is thoroughly rinsed to remove any remaining cleaning agents or loosened debris.
  • Verification:The effectiveness of the cleaning process is verified through testing to ensure that the SCR system is functioning optimally and meeting emissions standards.

The Importance of SCR System Cleaning

SCR system cleaning plays a significant role in maintaining diesel engines. First, it ensures compliance with emissions regulations by effectively reducing harmful nitrogen oxide (NOx) emissions from diesel vehicles. Compliance is crucial to avoid fines and penalties.

Second, a clean SCR system operates more efficiently, leading to improved engine performance, fuel efficiency, and overall vehicle reliability.

Third, regular cleaning prevents the buildup of deposits and residues that can degrade SCR system components over time, thus extending their lifespan and reducing the need for costly replacements.

Additionally, a clean SCR system promotes better fuel combustion and efficiency, resulting in improved fuel economy and cost savings for fleet owners.

Finally, by reducing NOx emissions, SCR system cleaning contributes to environmental protection and air quality improvement, mitigating the negative effects of diesel exhaust on human health and the environment.


Grey Ford Focus hatchback undergoing SCR system and DPF cleaning.
Ensuring peak performance: A grey Ford Focus hatchback receives SCR system and DPF cleaning to maintain optimal engine efficiency.

Revitalize your vehicle with 30 Minute DPF Clean! We specialize in professional DPF, DOC, EGR, and SCR cleaning & remanufacturing for a wide range of vehicles. Say goodbye to exhaust filter full warnings now. Get in touch with us today for comprehensive solutions.