The first direct injection engine made its debut when it was patented by an engineer named Rudolph Diesel in 1893.

Over time, people began developing injection systems. The first injection systems were developed for airplane engines at Mercedes and Bosch in Germany. Then, in 1950, Georges Regembeau adapted the technology to an existing car, the Citroën Traction.

The Mercedes 300 SL was the first car to come equipped with a standard injection system. Then came other models, such as the Peugeot 404 and 504.

The injector is a key component of any engine. In a direct injection engine, it is located by the cylinder inlet, and in an indirect injection engine it is located inside the intake manifold. The purpose of this part is to spread fuel using an atomizing spray method at the end of a compression cycle.

Functional principle of the injector

This fuel pump sends pressurized fuel to a common rail where the injectors are located; older systems have a cam that works the injectors, sending fuel into the combustion chamber in the form of a spray. In 1967, electronic injection made its debut; from here on fuel is electronically turned into a spray.

Injection via cams

Injection via cams

Electronic injection

Electronic injection

This system offers more precision in terms of the amount of fuel injected and injection time; it also reduces fuel consumption and polluting emissions, while at the same time increasing engine efficiency and performance.

Problems that arise

The injector can become clogged due to build up, low quality fuel and combustion residue which significantly reduces the amount of fuel injected; this, in turn, affects the air/fuel ratio and thus engine performance. The most common problems include:

  • Precarious slow motion
  • Lags in acceleration
  • A lack of power
  • Engine wheezing
  • Problems starting the engine

Examples of companies that manufacture injectors

Delphi, Bosch, fabricants injecteurs

The best solution

It’s helpful to replace the injectors, especially in four-cylinder engines. Before launching this operation, consider descaling: It cleans the injector nozzle, which is the part that is most exposed to build up and combustion residue. If you do, your engine performance will return to its original state.

Injector nozzle