Owning a diesel car requires a different set of knowledge than owning a gasoline model. Not only is diesel fuel 25% to 30% more energy rich than gasoline, it also uses a completely different injection model. If you are new to owning a diesel vehicle, you may not completely understand what exactly is happening when your car injects fuel.

From determining an LMM injector lifespan to replacing your Cummins injector nozzles, it is important to understand the following language. Start with these and add more as you go. By reading up on this diesel fuel injection system terminology, you can talk to any car professional about your diesel fuel injection system.

• Nozzle: One of the most important parts of your injection system, the nozzle actually provides a connection between the injection needle and the engine’s combustion chamber. This may be the part that you will replace most often.


• Start Of Delivery: This measurement varies in every vehicle. Start of fuel delivery is usually triggered by a certain pressure. This pressure builds as the car runs, and once it hits a certain point, the injection system sensors know to release fuel into the combustion chamber.


•  Injection Duration: This is the exact time period that the system uses to release fuel. Related is the injection pattern, which determines how often the system releases fuel.


• Timing Marks: These marks are located at different parts of the engine, flywheel, and damper to make sure that injection timing is happening correctly. If the marks are not aligned, timing could be calibrated incorrectly. This can mean trouble for your engine.


• Thermal Efficiency: Your mechanic may measure this to make sure your vehicle is using the perfect amount of energy. Thermal efficiency is how much fuel your car is using compared to the amount of fuel that is actually in the car.

If you have any questions about certain terms used by your mechanic, be sure to ask for clarification. Once you have your diesel vehicle for a while, you will get used to all of the moving parts and how they work together. You will learn, for example, how LMM injector life impacts injection duration. For now, continue to educate yourself so that you can identify any problems that come up by name.