A diesel fuel injection system differs from a gas engine in that the diesel fuel gets injected directly into the cylinder. In a gas engine, a port injection or a carburetor is used to inject fuel prior to the intake stroke (outside the cylinder) where the fuel mixes with air before it enters the cylinder.
The injector on a diesel engine is its most complex part. The pressure and heat within a cylinder are quite intense and the injector has to be able to handle those conditions while still distributing the fuel in a fine mist. Equally important, the mist needs to be distributed evenly throughout the cylinder. Some diesel engines use induction valves, pre-combustion chambers or another type of device to swirl air through the combustion chamber. This process helps distribute the fuel mist evenly and keeps the ignition and combustion process smooth.
Some diesel engines help the combustion process by using a glow plug, or some other device that helps keep the air temperature in the cylinder at a sufficiently high temperature. If the air temperature is too low, the fuel won't ignite. When the engine isn't running, it obviously gets colder; as a result, a glow plug (which looks like heated coils, like on a toaster) is needed to heat the air when the car is started. By keeping the air temperature high, the engine has a better chance of starting in cold weather.
Originally Published: Jun 16, 2011
Diesel Fuel Injection FAQ
What is diesel fuel injection?
A diesel fuel injection system directly injects diesel fuel into the cylinder. In a gas engine, a port injection or a carburetor is used to inject fuel prior to the intake stroke (outside the cylinder) where the fuel mixes with air before it enters the cylinder.
What is diesel direct injection?
A direction injection diesel fuel system injects fuel right into the combustion chamber at the top of the piston. This type of fuel injection system tends to use higher injection pressure and work more efficiently.
What does an injector do in a diesel engine?
The injector on a diesel engine is its most complex part. The pressure and heat within a cylinder are quite intense and the injector has to be able to handle those conditions while still distributing the fuel in a fine mist.
What are the two basic types of fuel injection systems?
Multiport fuel injection and throttle body fuel injection are the two most common fuel injection systems used in most passenger vehicles today.
Are all diesels fuel injection?
Yes, all diesel engines use a fuel injection system.AutoTypes of EnginesHow Diesel Engines WorkAutoHybrid CarsIntroduction to How Diesel-fueled Hybrids WorkAutoTypes of EnginesDiesel Engine PicturesAutoTypes of EnginesHow Diesel Two-Stroke Engines WorkAutoEngine PerformanceHow Diesel Fuel Injection Systems WorkAutoFuel ConsumptionIs diesel fuel better for the environment?AutoAuto BasicsDiesel Fuel Storage RegulationsAutoAlternative FuelsAfter Volkswagen: Where Does Diesel Go From Here?AutoFuel EconomyDoes a diesel engine equal fuel cost savings?AutoExhaust & EmissionsDiesel Isn't Always a Worse Polluter Than GasolineAutoHybrid TechnologyCalifornia Proposing Ban on Gas and Diesel CarsAutoTypes of EnginesIf diesel engines are more efficient, why do most cars have gasoAutoAlternative FuelsWhat's the difference between gasoline, kerosene, diesel, etc?AutoTypes of EnginesIs it true that a diesel engine can operate under water while aAutoTypes of EnginesDiesel Engines vs. Gasoline EnginesAutoTypes of EnginesUnderstanding the Cycle - The Diesel Two-Stroke CycleAutoEngine PerformanceWhy do big diesel engines and race car engines have such differeAutoAlternative FuelsWhat if I put diesel fuel in an automobile that required unleaded fuel?AutoTypes of EnginesDiesel Fuel - How Diesel Engines WorkAutoTypes of EnginesDiesel Fuel InjectionScienceEngines & EquipmentHow Diesel Locomotives WorkHistoryPost WW IISteam Versus Diesel
