Multi Point Fuel Injection System (MPFI) supplies the proper ratio of gasoline and air to engine cylinders without using a carburetor. It varies piston speed using advanced sensors controlled by the Engine Control Unit (ECU). MPFI systems are classified as either port injection or throttle injection based on the placement of the injectors. Port injection sprays fuel into the intake manifold near the intake ports, while throttle injection is similar to a carburetor with injectors controlling fuel mixing. The ECU primarily controls ignition timing and fuel injection quality based on sensor data. MPFI provides benefits like lower costs, higher efficiency, reduced maintenance, and higher engine power compared to carbureted systems.

1. Multi Point Fuel Injection System
(MPFI)
By,
Satha Siva Pandian . M
2nd year Mechanical Engineering

2. Introduction
•To Supply a proper Ratio of Gasoline and Air to
Cylinder.
•Without usage of Carburetor to mixing the Fuel and
air In SI Engine.
•Varied the Piston speed using Advanced sensors
(ECU).

3. Classification of MPFI
By the Placing of the injector it is further classified into two types.
I. Port Injection system .
II. Throttle Injection system

4. Port Type system
The Injector is Placed in the Intake Manifold near the intake Port .
The Injector Sprays Gasoline into the Air inside the manifold .
Fuel & Air mix in Uniform manner And this mixture Entered into
Cylinder .

5. Another design of Port Type system

6. Throttle Injection system
This is similar to carburetor Body with throttle valve
controlling the amount of Air entering intake manifold .
The sensor is used to control the fuel mixing level.

7. Type Of Injection System

8. Sketch of MPFI

9. 8 &12 Cylinder MPFI

10. Engine Control Unit (ECU)
In General ECU in turn is controlled by the Data Input
From the set of sensors Located all over the engine & its
Auxiliaries.
ECU primarily controls Ignition Timing & Quality of
Fuel to be injected.
ECU gives various commands to the Engine Fuel intake
system & Spark ignition system , To deliver an Over all
Satisfactory Performance of the engine From start to
Shut down including Emission Control .

11. MPFI

12. Advantages of MPFI
I. Without using of carburetor the product cost is Low.
II. Engine Efficiency is High.
III.Low Maintenance.
IV.High Power to Engine.
V.No extra Heating While Warm up. Etc,.

13. Disadvantage Of MPFI
1.Hood Height of the Car is High.
2.Manifold Heat control System OR Valve is Required.
3.Intake Manifold control only air not Fuel .

14. Throttle fuel injection system

15. Thank You!