These days, even 150cc powered engine bikes are equipped with fuel injectors for improving performance and fuel efficiency but with increase in cost.ġ. Uniform air-fuel mixture and higher fuel efficiency. Engine crank not necessary during cold startģ. But, MPFI with ECU which consists of many sensors acts as an intelligent system.Ī few advantages of MPFI over carburetor isĢ. In carburetor air-fuel mixture was a fixed ratio and hence right amount of fuel was metered resulting in excess burning of petrol resulting knocking/stalling and more pollutants to the atmosphere. MPFI is an advancement of carburetor technology but with an ECU in place. MPFI came into play as a means to meet emission norms set by various countries and in addition it also helps in deriving out good vehicle performance and minimum quantity of fuel.īefore MPFI, petrol engines were using carburetor type engines (used in commuter type bikes), which have become obsolete now. In simple terms, for the engine to produce power, proper amount of air-fuel mixture is required to be injected through the nozzle injector, which atomizes the fuel into tiny droplets into the combustion chamber, thereby spark plug ignites the mixture to propel the piston. Image1: Multi-Point Fuel Injection (MPFI) Engine M ulti P oint F uel I njection or Port injection system is used in petrol/gasoline engines (example – Maruti WagonR) in which each cylinder has a fuel-injector near the intake valve (Refer Image-I) and gets the name mulit-point based on the number of cylinders in the engine.
The main purpose of an injection system is to supply properly metered fuel to the combustion chamber via intake valve/port. First of all, before getting into knowing about MPFI (Multi-Point Fuel Injection) engine and CRDI(Common Rail Direct Injection) engine, please get to know the about the working of petrol and diesel engines.