This document discusses different fuel injection systems used in internal combustion engines, including the advantages of gasoline direct injection (GDI) over traditional carburetors and port fuel injection. It describes how GDI works by injecting fuel directly into the combustion chamber under high pressure, allowing for improved fuel efficiency and reduced emissions compared to earlier fuel delivery methods. The key components of a GDI system are an engine control unit, sensors, high-pressure fuel pump, and fuel injectors. GDI provides benefits like lower fuel consumption, increased power and torque, and helps engines meet tighter emission standards.

1. By – Shubham Sunil Badhe
Guidance By – Dr. S. I. Kolhe

2. INTRODUCTION
• Fuel injection is a system for admitting fuel into an IC
engine. It has become the primary fuel delivery system used
in engines, having replaced carburetors during the 1980s
and 1990s.
• FUEL INJECTION atomizes the fuel by forcibly pumping
it through a small nozzle under high pressure
• While a CARBURETOR relies on suction created by intake
air accelerated through a ventury tube to draw the fuel into
the airstream.

3. TYPES OF FUEL SUPPLY
 The Carburetor
 Single Point or Throttle Body Injection (TBI)
 Port or Multi Point Fuel Injection(MPFI)
 Sequential Fuel Injection (SFI)
 Direct Injection

4. THE CARBURETOR
• A device for atomisingand
vaporising the fuel and
mixing it with the air
• The process of breaking up
and mixing the fuel with air
is called carburation

5. Single Point or Throttle Body Injection
• The earliest and simplest
type of fuel injection
• Single-point simply replaces
the carburetor with one or
two fuel-injector nozzles in
the throttle body, which is
the throat of the engine’s air
intake manifold.

6. PORT OR MULTI POINT FUEL
INJECTION (MPFI)
• Multi-point fuel injection
provides a separate injector
nozzle to each cylinder, right
outside its intake port, which is
why the system is sometimes
called port injection.
• Shooting the fuel vapor this close
to the intake port almost ensures
that it will be drawn completely
into the cylinder.

7. GASOLINE DIRECT INJECTION
(GDI)
• GDI significantly improves fuel efficiency
without making a major shift away from
conventional IC technology.
• GDI is a process where fuel and air is sent
directly into the engine with high
pressure.
• The injector is connected along with the
intake valve, exhaust valve and the spark
plug.

8. GASOLINE DIRECT INJECTION
 The injector, injects the fuel according to the speed of the
engine. The intake valve is used for only air.
 Compression ratio is high as 12.5:1 at its peak value.

9. WHY NOT CARBURETOR??
 Carburetor has following Disadvantages:
 Vapour lock,
 Perfect air/fuel mixture cannot be obtained,
 Lack of throttle response,
 Low volumetric efficiency,

10. WHY THE GDI??
 Lower Fuel Consumption and More Output
 Better than the current MPI Style of Fuel Injection
 Ultra-precise computer management
 The location of the injector
 Less pollution from each drop of gasoline.
 The World needs a better Environment

11. GDI BURNING MODE
1. Ultra-lean burn mode: At lower speeds, the fuel is injected at
the end of the compression stroke for lowest heat losses. This is
when the compression ratio in the cylinders is maximum
2. Stochiometric mode: This is the conventional method of
injection during the intake stroke for optimum combustion
and minimum waste gases during moderate city driving
conditions.
3. Full Power mode: Fuel is injected in the intake stroke at a
higher .This is done at high speeds or high load conditions
like climbing a hill.

12. TIMELINE OF FUEL SUPPLY
SYSTEM
Carburetor Port Injection (MPFI) Direct Injection

13. ACHIEVEMENTS

14. MAIN COMPONENTS OF GDI
1. Engine Control Unit
2. Sensors
3. High pressure Fuel Pump
4. Fuel Injector

15. ENGINE CONTROL UNIT (ECU)
 ECU is a PROCCESOR of The Engine.
 ECU is computer that controls all of the electronic
Components on the engine.
 Working of ECU:
 Control of fuel mixture.
 Control of ignition timing.
 Control of idle speed
 Electronic valve control.

16. SENSORS
 In order to provide the correct amount of fuel for every
operating condition, the ECU has to monitor a huge number
of input sensors.
 Eg: Mass Air Flow (MAF) Sensor
Manifold Absolute Pressure (MAP) Sensor
Crank Angle Sensor

17. INJECTOR
 A fuel injector is nothing but an
electronically controlled valve.
 When the injector is energized, an
electromagnet moves a plunger
that opens the valve, allowing the
pressurized fuel to squirt out
through a tiny nozzle.
 It is controlled by the ECU.

18. ADVANTAGES
1. Engine Performance

19. 2. Vehicle Fuel Consumption

20. 3. Increased Volumetric Efficiency.

21. 4. Increased Compression Ratio

22. • Complexity
• High Cost
• Harder Deposit
• Undetected Knocking

23. GDI VEHICLE
 BMW
 Mitsubishi
 Volkswagen
 Ford- Eco Boost
 Hyundai- Lixus
 Mazda Speed

24. CONCLUSION
 Provide improved Torque 5-10%.
 Up to 5% more power.
 Reduction of carbon di-oxide by nearly 20%.
 Fulfils future emission requirements.
 97% Nitrogen oxide reduction is achieved.
 Reduced fuel consumption 15-20%.

25. THANK YOU