electronic injection system in ic engine....

2. Contents
 Background
• Why Gasoline Injection instead of Carburetion
• Type of Injection systems
• Components of Injection System
• EFI
• Sensors for EFI
• Merits and Demerits of EFI
• Multi-Point fuel injection
• Port Injection and Throttle Body Injection
• D-MPFI and L-MPFI
• Functional Divisions of MPFI
• Cold Start injector
• Injection Timing
• Group Gasoline Injection System

3. Background
 In 1903 Wright Brothers used SI powered Engine in
which gear pump mounted for injection.
 In 1906 Brazilian Santos Dumont made his first flight
in Europe with Plunger Pump injector.
 The last Carburetor that was installed in an American
automobile was in 1990
 Ford, Fiat, Mitsubishi, Daewoo and Honda etc have
come out with gasoline injection systems in their
models

4. Why Gasoline Injection instead
of Carburetion?
 In carburetor, uniformity of mixture is not same for
multi-cylinder engine.
 To overcome Maldistribution
 To improve breathing capacity( Vol. Efficiency).
 To eliminate Detonation or knock ( auto-ignition).
 To prevent fuel loss due to scavenging.
 Fuel Economy

5. Type of Injection systems
1. Diect injection: Injection in the inlet port directly.
2. Indirect injection ( port and Manifold injection)
 Continuous injection system: The air Fuel Mixture
is continuously made by sreamly injection
 Timed injection system: When the appropriate
pressure or requirement is achieved, injection takes
place.

6. Components of Injection System

7. Electronic Fuel Injector (EFI)
 A usually electronically-controlled system for injecting a
precise amount of atomized fuel into the cylinders or the
intake airstream of an internal combustion engine.
 In EFI sensors, computer systems and solenoid operated
fuel injectors are used.
 Injector Pulse: All modern automotive engines use
fuel injectors to deliver fuel to the combustion
chamber. It is simply the amount of time, measured in
milliseconds (ms), a fuel injector stays open (delivers
fuel) during a cylinder intake cycle.

8. Sensors for EFI
 Engine Temperature Sensor
 Air flow sensor
 Air inlet temperature sensor
 Throttle position sensor
 Manifold Pressure sensor
 Cam Shaft Position sensor
 Knock sensor

11. Multi-Point fuel injection
Divisions
 Port Injection
 Throttle Body Injection

12. Port Injection

13. Throttle Body Injection

14. D-MPFI

15. L-MPFI

16. Functional Divisions of MPFI
1. Electronic control system
2. Fuel system
3. Air induction system

17. Electronic control system

18. Fuel system

19. Injection Timing
 The timing at which injection takes place inside the
intake manifold is called the injection timing.
 For four cyliner engine, each intake manifold will be
fuel injected at specific times.
 If more power or acceleration is required, injection will
take more time for enough fuel.

20. Graphs
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1 1.05 1.1
Horsepower
Discharge Coefficient
Power vs. Discharge Coefficient
Gasoline
Light Diesel
Ethanol

21. 0
2000
4000
6000
8000
10000
12000
14000
16000
0 0.0002 0.0004 0.0006 0.0008 0.001 0.0012
Horsepower
Nozzle Area (m^2)
Power vs. Flow Area of Nozzle
Gasoline
Light Diesel
Ethanol

22. 0
2000
4000
6000
8000
10000
12000
0 50000000 100000000 150000000 200000000 250000000
Horsepower
Pressure Differential (Pa)
Power vs. Pressure Differential
Gasoline
Light Diesel
Ethanol

23. Conclusions
 Injection is superior to carburetion
 Indirect injection is easier and therefore more
common to implement
 Direct injection is more efficient
 Increasing the pressure differential across a fuel
injector is the most effective way to improve
performance
 Increasing the nozzle area is the easiest

24. References
http://en.wikipedia.org/wiki/Fuel_injection
 alternativefuels.about.com/od/glossary/g/injecpulsew
idth.htm
 IC Engines By V Ganesan