2. INTRODUCTION
A fuel injector is a component of a IC engine through which the delivery,
under pressure of a metered amount of fuel, as a fine spray, into the intake
airflow or combustion chambers of an internal combustion engine.
They have power continuously when the key is turned on.
Injectors open and close at the same rpm as the engine
Fuel injectors come in different sizes depending upon the cubic inches and
power demands of the engine.
4. Working principle
Fuel is suck by fuel pump from the tank at low
pressure with the help of filter.
Fuel is supplied to unit injector, where its pressure is
increased.
The high pressure fuel is then supplied to the engine
cylinders at appropriate time.
Any extra fuel goes again to tank through relief valve or
leak-off connector.
5. TYPES OF FUEL INJECTION
Throttle body injection
Continuous injection
Central port injection (CPI)
Multi-point fuel injection
Direct injection
6. TYPICAL FAILURES IN FUEL
INJECTORS
The following troubles appear concerning the fuel injector
Unstable idling.
Starting failure.
Insufficient output.
Deterioration of the exhaust gas.
7. Solution for the failure of fuel injectors
Electronic fuel injection(EFI): This combines sophisticated computer control with a
high pressure fuel delivery system to provide optimum power and fuel efficiency.
8. Advantages of efi
• A major benefit of EFI systems is the greatly improved
cold &hot starting performance
• Reduced fuel consumption & emissions.
• Eliminating carburetor float problems.
• Less servicing.
• The engine control unit (ECU) is the brain of the EFI
engine and the reason for many advantages of EFI.
