efi engine working procedure 

Describe Automotive EFI Engine working procedure  

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Presented By

Nur-E-Alam Siddike

ID:- 10307050

Program: BSME

Aim of EFI Engine

Get Maximum efficiency of engine power Ensure 100% fuel burn Reducing fuel cost Reducing air pollution

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How EFI Works?

• There are three sub-systems in EFIthe fuel delivery systemair induction systemthe electronic control system

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Fuel Delivery SystemThis system consist of the:

fuel tank,fuel pump,fuel filter,fuel delivery pipe,fuel injector,fuel pressure regulator, andfuel return pipe.

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The Air Induction System

This system consist of the:air cleaner,AIR FLOW METERthrottle valve,air intake chamber,intake manifold runner, andintake valve.

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Electronic Control System

This system consist of the:Electronic Control Unit (ECU),Various engine SENSORS,Fuel injector assemblies, and related wiringThe ECU determines precisely how much fuel needs

to be delivered by the injector based on the engine SENSORS output. Injector is turned On for the precise amount of time to deliver proper air/fuel ratio to the engine.

Electronic Control Unit

Uses electrical data from the sensors to control the operation of the fuel injectors.

Electronic Control Module (ECU or ECM)- “Brain” of the electronic fuel injection.

Various engine Sensor

Air flow meterThrottle positioning sensor

Various engine Sensor

Manifold Absolute Pressure Sensor (MAP)

Various engine Sensor

Oxygen sensorKnock sensor

Various engine Sensor

Air temp sensor Coolant temp sensor

Various engine Sensor

Cam shaft sensor Crank shaft sensor

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Basic Operation of ECU SystemAir enters the engine and then measured by the AIR FLOW

METER,As the air flows into cylinder, fuel is mixed into the air by

injector,ECU pulses the injector On and OFF. When it is ON just enough

spraying of fuel occurs, to ensure ideal air /fuel ratio 14.7:1(14.7 parts of air to 1 part of fuel by mass)

The ECU Control delivers precise amount of fuel to the engine, The injection quantity depend on variables such as:

coolant temperature engine speed (rpm) throttle angle, exhaust oxygen content.

Eletorinc Fuel Injection System

AdvantagesImproved Atomization Better fuel flow Smoother idle Increased engine powerImproved fuel economyLower emissions Better cold weather drivability Simpler

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Recommendation A better Knowledge and skills to install all of the necessary

sensors and wiring. Check for better performance. Adjust all the circuit and sensor with the ECU carefully. Before launce EFI system must test ECU with the help of

computer or testing devices. Should provide EFI profile and duration of it that how long it

work. Error must be checked & evacuated for precision of engine.

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ConclusionThe EFI increases the performance of the

engine.The EFI system is more economical and

produces greater powerAir pollution reducer and smoother drivability

than any other system.So we should use Electronic Fuel Injection

system (EFI) in every internal Combustion Engine.

Bibliography

1. YAHOO.ANSWER.COM2. GOOGLE.COM