What Is CNG Fuel? A Guide Explaining How CNG Vehicles Work

What is a CNG vehicle? They aren’t that common, but they're vehicles that are powered by natural gas instead of gasoline. The engine functions in the same way as a gasoline-powered combustion engine. Have you thought about what CNG fuel is?


In this blog, we briefly breakdown how CNG vehicles work. 


Explaining CNG Engines


We explain step by step how your CNG vehicle breaks down natural gas into fuel: 


1.) CNG is compressed to 3600 psi and enters the vehicle through the CNG fill receptacle.


2.) It flows into high-pressure cylinders located in or under the vehicle.


3.) For a bi-fuel NGV, the vehicle will operate on CNG vehicles until the fuel runs out; then, it will switch to gasoline until the CNG tank is refilled. A fuel selector on the dash permits the driver to manually override the system and switch between CNG or gasoline. A dedicated NGV operates solely on CNG.


4.) When needed the CNG leaves the cylinders and passes through the (PRD) pressure relief device and electric solenoid shut-off valve (Which stops the flow of CNG fuel when the engine is not running or in the case of a bi-fuel vehicle, gasoline is selected).


5.) The CNG fuel travels through a short high-pressure fuel line and enters a (10 micron) coalescent filter, which removes oil droplets and other contaminates from the CNG.


6.) The CNG now enters the pressure regulator, which reduces pressure from up to 3,600 psi to approximately 70 - 125 psi.


7.) The CNG flows through a low-pressure fuel line and enters the fuel rail, which supplies pressurized fuel to all the specially designed CNG fuel injectors.


8.) The CNG injectors inject the CNG into the engine’s cylinder intake valves.


9.) The ECM (electronic control module) controls the sequential multi-port fuel injection pulse widths or amount of CNG fuel the injectors inject into the engine. This system allows each cylinder’s injector to open just before the intake valve opens.


Choose Advanced Vtech 


Every vehicle needs regular maintenance. If you need any automotive services for your CNG vehicle, book a service appointment today in Buffalo Grove. To learn more about what CNG fuel is and how to maintain your car’s engine, you can explore our blogs. 


Source: Altech-Eco

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