The history of emission controls like Exhaust Gas Recirculation (EGR) valves and their importance in the proper operation of the vehicles using them.
Ken Coleman is an ASE Master Technician at Great Falls Auto Repair in Great Falls, Montana who knows a lot about emission controls. For more than 50 years, emission control systems have been working to reduce the impact of vehicle emissions like Nitrogen oxides (NOx), which are produced in the combustion processes inside gasoline engines, partly from nitrogen compounds in the fuel, but mostly by direct combination of atmospheric oxygen and nitrogen in flames. Auto manufacturers have traditionally reduced NOx emissions through the use of exhaust gas recirculation through EGR valves, but that’s changing.
In this episode of the ATI Podcast, we’ll talk with Ken about the history of emission controls like EGR valves and their importance in the proper operation of the vehicles using them. Knowing how these devices work and some common failure modes will not only increase your diagnostic capabilities, it will give you a heads-up on what’s next in emission control technology. Listen in as Ken shares his insights on:
- Why emission controls were introduced to initially control crankcase vapors.
- How EGR valves help control NOx emissions and how they work.
- How both mechanical and electronic controls are used on EGR valves.
- How valve timing uses valve overlap to control NOx .
- Typical failure modes for EGR valves.
- How different manufacturers use different control strategies for EGR.
- How electronic controls work and differ from mechanical systems.
- What you need to know when diagnosing EGR system failures.