EPA Tells Diesel Engine Makers to Ditch One of the Most Unreliable Emissions Components
The Drive • • business
Key Points:
- The U.S. Environmental Protection Agency (EPA), under Administrator Lee Zeldin, is shifting towards deregulation of diesel emissions, encouraging manufacturers to eliminate power derating when diesel exhaust fluid (DEF) runs low and reconsider the use of urea quality sensors.
- The EPA highlighted that urea quality sensors, which detect urea concentration in DEF to control NOx emissions, have some of the highest failure rates among selective catalyst reduction (SCR) components, causing engine performance issues and warranty claims.
- The agency supports exploring alternative detection methods, such as NOx sensors, and states that removing urea quality sensors is not considered tampering under the Clean Air Act if replaced with effective solutions, though emissions system deletes remain illegal.
- Challenges remain, including sensor performance in cold climates where DEF can freeze, prompting some lawmakers to advocate for relaxed DEF requirements in certain regions, but there are no current plans to deregulate DEF use entirely.
