Fuel Injector: Description and Operation

Fuel Injector:

PURPOSE
Fuel injectors are solenoid operated valves that meter fuel flow to the engine.

LOCATION
Top of intake manifold near cylinder head.

OPERATION
Injectors are turned ON/OFF by the Electronic Control Assembly (ECA). Regulated fuel pressure is variable depending on intake manifold vacuum. Quantity of fuel to the engine depends on fuel pressure and how long injectors are ON.

CONSTRUCTION
The injector valve body consists of a solenoid actuated pintle or needle valve assembly that sits on a fixed size orifice.