Diesel SCR Systems Explained: How to Diagnose and Replace a NOx Sensor

Diesel SCR Systems Explained: How to Diagnose and Replace a NOx Sensor

In this video we are going to take a look at the Selective Catalyst Reduction System in a modern diesel vehicle because my 2.8 Duramax Colorado has developed a P11DB NOx Sensor Performance code. I'll start by explaining what NOx or Oxides of Nitrogen are and how they pertain to a diesel engine.

Once you understand what NOx is I'll talk about how Diesel SCR systems work, including their key components and overall function. Learn about the critical parts that make up the system and how they contribute to reducing emissions.Once you have a basic understanding of how the Diesel SCR system works we will start to diagnose the NOx Sensor code that I'm dealing with on this truck and what exactly causes these sensors to fail.

Links to Parts/Tools used in this video:
Idash: https://amzn.to/47gPUls
Ammonia Glass Cleaner: https://amzn.to/4gj2qVG
Test Light: https://amzn.to/3AW7j7b
Oscilloscope: https://amzn.to/3TjXXsf

OEM NOx Sensors:
16-18 2.8 Duramax UPSTREAM: https://amzn.to/4guAbDV
16-18 2.8 Duramax DOWNSTREAM: https://amzn.to/3ASf1iH
19-22 2.8/3.0 Duramax UPSTREAM: https://amzn.to/4dZcvpy
20-23 6.6 Duramax UPSTREAM: https://amzn.to/3XgdCtx
20-23 6.6 Duramax DOWNSTREAM: https://amzn.to/3XfGFO6

I was not able to find any OEM Ford NOx Sensor on Amazon.

13-15 6.7 Cummins Downstream: https://amzn.to/3ZbctWU

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I source all of my service data from the same place that professional shops do. You can as well: https://www.pntrac.com/t/SENKSUZKRktD...

Questions? Shoot me an email at [email protected]

Chapters:
00:00 Intro
00:04 What is wrong with my truck?
1:46 Disclaimer: "Just delete it"
2:48 What is the SCR System?
4:30 How does the SCR System Function?
7:11 What is De-Rate?
8:42 Reading the NOx Sensor datastream
9:41 Attempting to diagnose a NOx sensor
14:19 What causes a NOx sensor to go bad?
15:21 NOx Sensor removal
19:36 Resetting the sensor values in the ECM.
21:14 Test drive after the repair
22:10 What can you do to prevent a NOx sensor failure
24:19 Outro

#diesel #emissions #nox #EPA #dieselengine #repair #diagnosis

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