What is the role of the EGR Exhaust Gas Recirculation system in Prius emissions, and why does it fail?

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What is the role of the EGR Exhaust Gas Recirculation system in Prius emissions, and why does it fail?

The EGR system helps reduce NOx emissions, but over time, carbon buildup can clog the EGR valve and cooler, leading to performance issues. Discussing how to clean o r replace the EGR system can improve emissions and fuel efficiency.

Zarnish asked on 13 Feb 2025 12:36:57 pm

1 Answer

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Car Mechanic Expert - on 13 Feb 2025 12:45:12 pm

The Exhaust Gas Recirculation EGR system reduces nitrogen oxide NOx emissions by recirculating a portion of the exhaust back into the engine’s intake.

Why It Fails:
Over time, carbon buildup can clog the EGR valve and cooler, causing performance issues like poor engine efficiency and increased emissions.
Failure to address EGR problems can also lead to rough idling, engine knocking, o r increased fuel consumption.

Solution:

Regularly clean the EGR valve and cooler to prevent carbon buildup.
If cleaning doesn’t help, consider replacing the EGR components.