Fuel Injector: Description and Operation

- The MFI system employs a top feed type fuel injector with air assist system.
- The top feed type fuel injector is installed in the fuel pipe to allow cooling of the injector by the fuel.
- The features of this type of fuel injector are as follows:
1. High heat resistance
2. Low driving noise
3. Easy to service
4. Small size

- The fuel injector injects fuel according to the valve open signal received from the ECM.
- The nozzle is attached on the top of the fuel injector. The needle valve is lifted by the solenoid coil through the plunger on arrival of the valve open signal.
- Since the injection opening, the lifted level of valve and the regulator-controlled fuel pressure are kept constant, the amount of fuel to be injected can be controlled only by the valve open signal from the ECM.
- Fuel is atomized using air supplied from the idle air control solenoid valve, which contributes to not only higher combustion efficiency and higher output but also cleaner exhaust emission.