MULTI POINT FUEL INJECTION SYSTEMBY: GOURAV GUPTA ROLL NO. 12 ENROLLMENT NO. 71/09
INTRODUCTION MPFI- a technology used in petrol engines Uses a small computer to control the cars engine
In MPFI engine one fuel injector is installed near each
cylinder ,that is why it is called multi point fuel injection. Before MPFI system, there was a technology called
The computer in the MPFI system decides what
amount of fuel to inject System also learns from the drivers driving habits MPFI system makes engine fuel efficient
OBJECTIVES power output fuel efficiency emissions performance reliability drivability and smooth operation initial cost maintenance cost range of environmental operation
SUPPERSESSION OF CARBURETORS Extensive carburetor modifications and complexities were needed to approach stoichiometric engine operation 3 primary types of toxic emissions from an IC engine: CO, unburnt HC, and NOx5
Fuel injection systems have significantly evolved
since mid 1980s. Current systems provide an accurate, reliable and
cost-effective method of metering fuel and with clean exhaust emissions-replaced carburetors in the marketplace The carburetor remains in use in developing countries
COMPONENTS OF MPFI SYSTEM Air intake system
Fuel delivery system Electronic control system
AIR INTAKE SYSTEM Throttle Body consist of throttle valve, T P sensor, which detect the throttle valve opening.
Ideal Air Control Valve supplies bypass air depending on the engine condition.
FUEL DELIVERY SYSTEM Fuel Pump consists of armature, magnet, impeller, brush, check valve etc.
Pressure Regulator System keeps the fuel pressure applied to the injector higher than intake manifold at all times.
Fuel Injector injects fuel into the intake port of the cylinder head according to the signal from ECM
ELECTRONIC CONTROL SYSTEM Electronic Control Module controls various devices according to the signals from the sensors.
Fuel Injection Control System supplies the combustion chambers with air/fuel mixture of optimized ratio under widely varying driving conditions.
Fuel Pump Control System ECM controls ON/OFF operation of the fuel pump11
Ignition Control System system controls electronically the time of electric current flow to ignition primary coil as well as ignition timing.
Radiator Fan Control System controls operation (ON/OFF) of the radiator fan motor
SENSORS USED IN MPFI SYSTEM Exhaust air or oxygen sensor Engine coolant temperature sensor Inlet air temperature sensor Air flow sensor Throttle position sensor Manifold pressure sensor
Camshaft position sensor Crankshaft position sensor
VARIOUS INJECTION SCHEMESMPFI system
Throttle Body injection
Port Injection The injector is
placed on the side of the intake manifold near the intake port Every cylinder is
provided with an injector in its intake manifold
Throttle Body Injection System
CONCLUSION Improved fuel consumption Better for the environment Better performance
Referenceswww.howstuffworks.com www.indiacar.com www.carblogindia.com www.indiacar.com www.wikipedia.org www.crazyengineers.com www.ehow.com www.google.com (for images)