EFI means Electronic Fuel Injection system and it replaces the carburetor on the internal combustion engines in modern vehicles. It comes with injectors as well as a fuel pump. It exactly calculates the fuel that is delivered to the cylinders thereby it optimizes the performance of the engine and reduces the consumption of fuel in compliance with emission standards across the world. Until the introduction of EFI, the fuel delivery was timed by the mechanical devices. With the introduction of EFI, the electromagnetically controlled injectors take care of the fuel delivery system. There are different types of EFI namely, throttle body injection, single point fuel injection and central point fuel injection and all these uses single injector to inject fuels into various cylinders. The most common injection type is port or multi point fuel injection in which there is one injector per cylinder for injecting fuel into the cylinder. Again, the multi-point Fuel Injection (MPFI) could be divided into different types. Continuous injection delivers fuel into the cylinder with a steady flow whereas the sequential injection is timed to deliver the fuel as when the intake valves open. EFI provides benefit like easy starts, improved load pick up, optimal performance and lower fuel consumption.