Vehicle Training Level 3 Heavy-Duty NGV Maintenance and Diagnostics Training

The number one challenge facing heavy-duty NGV technicians is how to distinguish between a fuel quality problem, a fuel system problem or an engine problem. This course is the only training available that treats these three elements as a system and helps technicians understand how they are interrelated.  Emphasis is placed on the safety knowledge and repair practices that are unique for Cummins heavy-duty natural gas engines. 

The course covers the components of all CNG fuel systems (regardless of manufacturer), as well as all Cummins 6.7 Liter, 9 Liter and 12 Liter natural gas engines.

The course includes operational theory with more than a dozen hands-on exercises. It is a perfect prerequisite to fuel system or engine manufacturer training. This course also helps prepare technicians for the ASE H1 exam.


NGV Essentials and Safety Practices

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Salt Lake City, UT March 30, 2020 Register

Who Should Attend?

  • Technicians with at least basic skills in heavy-duty vehicle repair, who will be maintaining, diagnosing and repairing NGVs.
  • Technicians familiar with the basic operation of vehicle diagnostic equipment.

Course Objectives

  • Describe the maintenance, diagnostics, and repair recommendations for the low- and high-pressure components of a CNG fuel system
  • Identify the unique components and explain the operation of the Cummins 6.7 liter, 9 liter and 12 liter natural gas engines and emissions control system
  • Outline engine component maintenance intervals and procedures unique to Cummins powered NGVs
  • Understand basic diagnostic procedures for Cummins 6.7 liter, 9 liter and 12 liter natural gas engines
  • Interpret data for electrical related issues using wiring diagrams and other tools
  • Diagnose hard starting and/or poor drivability issues
  • Identify unique components and understand the operation of LNG (saturated) and HPDI (unsaturated) LNG fuel systems
  • Prepare technicians for successful completion of the Cummins ISL G and ISX12 G engine certification and/or the ASE H1 Alternative Fuels certification exam

Course Outline

Module 1 Introduction
Module 2 Properties and Safe Handling of Natural Gas Review
Module 3 High-Pressure CNG Fuel System Maintenance and Diagnostics
Module 4 Low-Pressure CNG Fuel System Maintenance and Diagnostics
Module 5 CNG Vehicle Depressurizing and Defueling
Module 6 Cummins ISX12 G Engine Operation and Diagnostics
Module 7 Cummins ISX12N Engine Operation and Diagnostics
Module 8 Cummins ISL G and L9N Engine Operation and Diagnostics
Module 9 Cummins ISB6.7 G and B6.7N Operation and Diagnostics
Module 10 Cummins Natural Gas Engine Maintenance and Required Tools
Module 11 LNG Fuel System Components and Operation
Module 12 Activities and Labs


Instructional staff members of colleges, universities, private training organizations, fleets, dealers or manufacturers are not candidates for this course, but have numerous options for bringing NGVi’s training classes to their campuses or facilities. For more information, contact us at 800-510-6484.