Basic Configuration

• The basic configuration of fuel injectors is the same. They consist of a body with an opening at one end and an attachment to the fuel pipe, or rail, at the other. The body is wrapped in electrical wire to create a solenoid, or mechanical switch, which pulls a stopper out of the opening to inject fuel.
  
  

Housing

• The housing of fuel injector nozzle is typically made from brass. The housing contains brass or stainless steel inserts, with holes that vary in diameter according to the exact specification of the engine. In many cases, nozzles are threaded into the engine cylinder at the intake port with pipe thread, although straight thread and a copper crush gasket is another possibility.
  
  

Bleed Screen

• In normally aspirated engines -- engines without a turbocharger or supercharger -- fuel nozzles are usually equipped with a so-called bleed screen, made from stainless steel. The screen filters the air entering the body of the fuel nozzle.