Types of fuel Injection system in petrol engine are many and today we will talk about the differences among them. So today we will discuss about the different types of petrol engines according to the different fuel injector systems. We will see why different fuel injection system was needed. How these different fuel injection system evolved with time. Which engine do we regularly use today and which one is having longer life.
What are the types of fuel injection systems?
First of all we have to see what is a fuel injection system. The fuel injection system basically need in Internal combustion Engines which we know as ICE in short. These engines need oxygen and fuel to get the fuel burn fully and efficiently. So there are different system whose work is to pass the fuel inside the engine. Here are the types of fuel injection systems
- Carburetor– It is a device which prepare air and fuel mixture and send it to engine’s cylinder. This technology was developed in 1875 for petrol engines. Air flows from inside the carburetor and due to which there is a lower air pressure which help in fuel suction. This fuel gets mixed inside and sent to the cylinder. After 1980 this system got obsolete the reason is the use of new technology like electronics in cars. The limitation of the carburetor is that we do not have a precise control on fuel being inserted due to which power requirement was not getting fulfilled. Also the carburetor system was less efficient there was higher amount of fuel getting waste. So the fuel injection technology came into picture. Todays after 1980’s not a single car is equipped with the carburetor device, neither a smallest car have the carburetor based system today. now what type of technology is used in todays time.
- Throttle Body Injection– There came throttle body injection system developed by Bosch in 1952. In this technology the Throat through which the fuel was getting inserted was replaced by an Injector. This saved fuel and increased efficiency because due to the injectors the wastage of fuel was less. The minimum electronics was used in this system. After the adoption of this technology it was noticed that pollution was under control. Cost increased but power output remain less. So this technology was not proved very successful.
- Fuel Injection System– The technology was used in the Diesel cars earlier but later this technology was shifted to the petrol engines also. After the 1980’s we are doing the fuel injection using an injector. Using the fuel injectors the fuel is directly gets injected to the cylinder or in Intake manifold and fuel gets burn with high efficiency. here is a different fuel injector and fuel nozzle too which help in injecting the fuel inside.
- MPFI/MPI Engines (MultiPoint Fuel Injection)– After 1990 there was a revolution when MPI injections came to effect. MPI stand for multipoint injection system, or MPFI multipoint fuel injection system. This became so much popular that after 1998 is was being used widely in the world. In MPI engines there are different injectors for different cylinders fitted in Intake manifold. For example 4 cylinder engine will have 4 injectors. These injectors are connected with the ECU (Engine Control Unit) which electronically calculate how much fuel has to pass to the cylinders to get efficient burning. The limitation of the MPFI engines is that these can not be used with a turbocharger.
- GDI (Gasoline Direct Injection)– After some time in 1996 Mitsubishi developed the GDI technology of fuel injection. GDI means Gasoline Direct Injection (Gasoline means petrol). The injectors inject fuel directly on the cylinder head unlike on the port as in MPFI. So in this technology there must be a higher pressure in the injectors (used to inject fuel) than the pressure inside the cylinder during the compression stroke.
Due to which the Injectors used should be of a better build quality, The injector should be a high pressure injectors which can withstand high temperature also so they have high pressure fuel pump for injectors. that is why GDI becomes much costly.
GDI engines are costlier than the MPFI engines, only some top models which have turbocharger will have this GDI technology. The benefits of using GDI over MPFI is higher fuel economy by allowing most fuel to burn, allows high compression ratio for higher efficiency, less fuel needed in acceleration as compared to MPFI, 10-15% reduction in fuel exhaust emission, so in todays time all the turbo cars is equipped with GDI and the normal manual and some lower variants are having MPFI technology.
Also Read: Maintain A turbocharger Engine
- TSI (Turbocharged Stratified Injections)– Some particular types of companies are there which uses a different technology for their turbocharger engines namely TSI. These are VW, Skoda and Audi. This type of fuel injection is compulsorily used for a turbocharged engines only, GDI tech is also similar to TSI but the GDI is not compulsorily used for a turbocharged engines. In TSI engines fuel is injected directly to the cylinder same as GDI. But an Intercooler is must used by a TSI engine. Because of the involvement of the turbocharger there is a higher heat generation so for cooling purpose Intercooler is used. Also in the petrol engines, there is a chance of Knocking due to High Pressure and High Temperature in the cylinder so the intercooler is used. But GDI engine are free from the intercooler system. GDI technology is a Japanese technology and the TSI is a German technology. So they claim the TSI is more powerful than GDI.
Which car has an MPFI engine?
Almost all cars which are not turbocharged are having MPFI engine technology today. The MPFI involve the multipoint fuel injection system which increases efficiency and help in decreasing the pollution. Because this is not much costly the lower segment, manual car variants have this type of technology system. Being modern but also it is reliable and have low maintenance.
Is MPFI engine good or bad?
The MPFI engines are good for mediocre performance cars. It is safer to use because it is todays technology very efficient and reliable too. This help in less knocking and less chance of misfire in the engine. The MPFI engine gives smoother ride quality and it is a long term well performing technology. The fuel injectors used are also normal type unlike high pressure fuel injector used in GDI engines. So they are cost efficient too.
Which cars have GDI engines in India?
All the turbocharger cars will have GDI technology and GDI engines in India. Only VW, Skoda and AUDI groups use own developed technology for their turbocharged engines which they call it TSI engines. For example Hyundai, Tata, Mahindra uses GDI technology for their Turbo variants
MPFI vs GDI Which Is better?
It is based on the technology and the compatibility. The MPFI engines are good for average performance cars. It is safer because it is less expensive, very efficient, reliable and low in maintenance. As there is less chance of carbon pileup issues. But limitation is that it can not be used for a Turbocharged engines.
So the role of GDI engines becomes important here. GDI is compatible with turbo. This is more fuel efficient and more performance oriented technology. But it is more complex and expensive too. Because high quality of injectors that can tolerate high temperature and high pressure are required for GDI engines.
Also Read: GPF Issue in Petrol Cars
What is TSI GDI engine?
TSI tech is similar to GDI. In TSI engines fuel is injected directly to the cylinder same as GDI. But TSI has some difference.
- TSI must only be used with a turbocharger engines but the GDI is not compulsorily be used with a turbocharged engines. It can also be used without a turbocharger.
- An Intercooler is must in a TSI Engine. Because of the involvement of the turbocharger there is a higher heat generation so for cooling purpose Intercooler is used. But GDI engine are free from the intercooler.
- GDI technology is a Japanese technology and the TSI is a German technology. So they claim the TSI is more powerful than GDI
- The TSI tech is mostly expensive so GDI is used more in the cars.
