Petrol vehicles uses device called carburetor for supplying the air fuel mixture in correct ratio to cylinders in all rpm ranges. due to construction of the carburetor is relatively simple, it has been used almost exclusively on gasoline engines in the past. However in response to recent demands for cleaner exhaust emission, more economical fuel consumption, improved drivability, etc., the carburetor now must be equipped with various compensating devices, making it more complex system.
So In place of the carburetor, therefore, the MPFI (multi point fuel injection) system is used, assuring proper air fuel ratio to the engine by electrically injecting fuel in accordance with various driving conditions.
MPFI system injects fuel into individual cylinders, based on commands from the ‘on board engine management system computer’ – popularly known as the Engine Control Unit/ECU. These techniques result not only in better ‘power balance’ amongst the cylinders but also in higher output from each one of them, along with faster throttle response. The electronic fuel injection system supplies the combustion chambers with air/fuel mixture of optimized ratio under widely varying driving conditions.
ADVANTAGES OF MPFI
- More uniform A/F mixture will be supplied to each cylinder; hence the difference in power developed in each cylinder is minimum. Vibration from the engine equipped with this system is less, due to this the life of engine components is improved.
- No need to crank the engine twice or thrice in case of cold starting as happens in the carburetor system.
- Immediate response, in case of sudden acceleration / deceleration.
- Since the engine is controlled by ECM* (Engine Control Module), more accurate amount of A/F mixture will be supplied and as a result complete combustion will take place. This leads to effective utilization of fuel supplied and hence low emission level.
- The mileage of the vehicle will be improved.
Almost all vehicles in India are changing to the mpfi because of law emissions, improved mileage and drivability since the engine is controlled by micro computer more accurate amount of a/f mixture will be supplied and as a result complete combustion will take place. this leads to effective utilization of fuel supplied and hence low emission level. it reduces wastage of fuel by the use of sensors and other control systems