How Does a Single Injection Engine Work?

Fuel injection simply refers to the means by which fuel is added to internal combustion engines, typically gasoline engines for cars. It has been the number one fuel delivery system for automobiles for many years, replacing the carburetors that used to be used through the late 90s. There are many different types of fuel injection systems that can be used successful.

Fuel injection systems atomize fuel so that fuel can be pumped through nozzles that are under high pressure. 

Single Point Injection Systems

The single-point injection system uses a single injector as the name implies, located at the throttle body or part of a vehicle where that controls how much air flows into the engine. It is also referred to as part of the air intake system on a vehicle. This system responds directly to how much pressure a driver puts on the accelerator pad on the car. This is sometimes located near the air filter and intake manifold, and may be located near a sensor. 

The single injection system was first used in the 1940s, largely by aircrafts, and often called pressure carburetor systems. General Motors first called the single point injection system the throttle-body injection; Ford referred to it as “central fuel injection” and Mazda called it the “EGI” system. 

Using this type of fuel injection, gas passes through intake runners much like it would a carburetor, thus it is a wet manifold fuel injection system. One of the reasons this system has been popular is that it was low-cost. The supporting parts for it including the air filter, cleaner and intake manifold could be used again. This system was highly used through the mid-1990s and can still be found on many vehicles.

More commonly now are directly injection systems and diesel engines which allow fuel to be injected directly into the combustion chamber.