Aftertreatment and Emissions Systems
Since 2007, the EPA has imposed restrictions requiring every on-highway diesel vehicle to have some type of aftertreatment system to clean the exhaust expelled by diesel engines. Unfortunately, these systems have high failure rates and rely on the health and functionality of the engine, ultimately making it challenging to diagnose these failures and find the root cause of it. In this class, you'll learn how understanding the interaction between upstream engine issues and aftertreatment system issues can quickly get to the root cause.
All courses are led by experienced, certified diesel technicians.
Aftertreatment System Components
You'll learn the function, operation, and the internal view of the diesel oxidation catalyst (DOC), diesel particulate filter (DPF), selective catalytic reduction (SCR) system, and aftertreatment fuel injectors and their alternative names.
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Regeneration System Operation and Diagnostics:
- Engine controls that regulate the DOC inlet temperature during regeneration
- How to spot low temperature issues during regeneration
- How to clean DPFs and DOCs and inspect them for replacement when removed
SCR System Operation and Diagnostics:
- What diesel exhaust fluid (DEF) is and the importance of verifying concentration with a refractometer
- DEF system operations including pumps, tanks, lines, tank and line heaters, decomp tube, and dosers
- Particulate matter sensor function and operation
- How to address aftertreatment and SCR derates, including what they mean and how certain manufacturers require you to clear them.
Actuators Affecting Aftertreatment:
- Turbocharger and related components (How low boost can cause regeneration issues)
- EGR valve and related components (How EGR function can cause regeneration issues)
- Fuel systems and related components (How fuel-related issues can cause regeneration issues)
- How low power, oil consumption, smoke, and cylinder performance affect aftertreatment
No Fault Codes?
Sometimes a fault code isn't available to help with diagnosing issues with aftertreatment systems. To make diagnosing without a fault code easier, you'll learn about regeneration temperature diagnostics and the cause of regeneration temperature inversions.
Oil Dilution and Regeneration
Our instructors will explain the differences between post-injection and in-cylinder regeneration operations. You'll also learn about oil and fuel dilution issues and byproducts of them.
Injector Programming and Regeneration Issues
You'll learn about the importance of IQA or injector coding when replacing an injector and how it could potentially affect the aftertreatment system.
To reinforce the concepts learned in this course, you'll perform hands-on labs with learning aids developed by our training department. We'll also perform a live regeneration to validate the concepts learned during the lecture portion of this course.
Benefits for Diesel Technicians
You'll sharpen the skills necessary to simplify diagnosing these seemingly complex systems. This knowledge will help you diagnose vehicles all across the board as this training is not specific to any one manufacturer, and we go over most variations you'll find.
Benefits for Shop Owners and Managers
The skills your technicians learn in this class will help them diagnose equipment quickly and efficiently, resulting in less time wasted on incorrect diagnostics and repairs, ultimately leading to less downtime. Your customers will be breaking down your door when they find out how quickly you can get them back up and running.
Until further notice, students attending our in-person training classes at any location will be required to undergo a mandatory non-contact temperature check before entering the classroom. Optional masks will also be provided to students.