Few car owners know what it is - an MPI engine. This abbreviation stands for Multi-Point-Injection, and the motor itself is a design with a multi-point fuel injection system. To summarize the data, the peculiarity of such a motor is that each cylinder of the power plant receives its own injector nozzle. This technology was developed and implemented
Where is it implemented?
Now you understand a little what is an MPI engine. For the first time, such technology was successfully implemented in the Polo model. Later "Golf" and "Jetta" also received such engines.
Note that such engines are outdated from the engine range. However, they are practical and reliable. Many experts argue that today such power plants do not meet modern standards of efficiency and ecology. In addition, quite recently one could say that the manufacturer stopped the production of such motors. The last car that received the MPI engine was the Skoda Octavia of the second series.
However, recently the technology has been revived, it has become in demand. In the fall of 2015, the concern launched a production line for these engines at the Kaluga plant, where they began to produce EA211 series engines.
Peculiarities
About what features they have, it has already been written above. These are engines with a multi-point gasoline supply system. However, people in the know can say that TSI engines also use a multi-point fuel supply system. Therefore, in this case, it is appropriate to talk about other distinctive features - there is no supercharging in the Skoda and Volkswagen MPI engines. This means that there are no turbochargers that would force the fuel mixture into the engine cylinders. It uses the most ordinary gasoline pump, which pumps gasoline from the tank to the start manifold, while creating a pressure of only 3 atmospheres. In the manifold, the fuel mixes with air and is drawn into the combustion chamber through the intake valve. Actually, the system is very similar to the principle of operation of a carburetor, and there is no direct fuel injection into the cylinders (as in FSI, TSI and GDi engines).
Now you have a better understanding of what MPI engines are. It is appropriate to answer the second feature - the presence of a water cooling system. Thanks to it, the fuel is cooled. This is necessary due to the increased temperature regime at the cylinder head. Since the temperature is high there and the fuel is supplied at low pressure, there is a possibility that the fuel mixture may boil, which will lead to the formation of gas air pockets.
Advantages
MPI motors boast unpretentiousness to the fuel used and work effectively on 92nd gasoline. Also, the design of such an engine is very durable, and its mileage without any intervention and repair averages 300 thousand kilometers. Of course, it is necessary to change filters and oil on time. 1.6 MPI (and other car models) is simple in design, and in the event of any breakdown, it can be inexpensively repaired at a service station. In this case, the design feature of such engines compares favorably with more complex TSI engines with high pressure pumps and turbochargers. Also, MPI motors overheat less.
The last more or less relevant plus is the rubber mounts located under the engine. They help reduce noise and shaking while riding.
Minuses
According to the reviews, MPI engines are less dynamic, and there is a reason for this. Due to the fact that gasoline is mixed with air in the exhaust channels (before it enters the cylinders), these engines are limited. Also, the eight-valve system with a timing kit makes it clear that the motor lacks power. Therefore, such engines are not designed for a quick start and speed gain.
The second drawback is uneconomical. Multi-point injection is inferior in efficiency and economy to supercharging with direct injection of fuel into the cylinders. As mentioned above, this technology is implemented in TSI engines.
MPI engine - a solution for Russian roads
In addition, cars with such engines are better suited for Russian operating conditions. The fact is that the quality of the fuel sold at some gas stations leaves much to be desired. However, for MPI engines, even gasoline with a higher sulfur content is easily perceived, and the engine processes this type of fuel perfectly. And the robust design of the power plant itself provides additional reliability and protection against excessive mechanical stress that occurs when driving on bad roads with potholes. So it can be rightly noted that MPI engines are better suited for Russia. Perhaps because of this, a production line for the production of such motors was established at the Kaluga plant. Now we have finally figured out what an MPI engine is and what are its features, advantages, and disadvantages.
Finally
If we compare the pros and cons, we can conclude that such motors are quite competitive. An indirect confirmation of this is the refusal of German manufacturers from 1.2-liter TSI engines in favor of unpretentious 1.6-liter engines with MPI injection technology.
Can it be recommended to car buyers? Quite! This is quite a successful technology from the concern "Volkswagen", which deserves a chance at life. Numerous customer reviews confirm this.
Surely everyone knows what a motor is in a car. but today our article is devoted to a specific unit, about which we will try to tell from "A" to "Z"
The end of the last century and the beginning of a new one became a period of heightened interest in gasoline engines brand MPI. The decoding of this abbreviation sounds like Multi Point Injection. An extraordinary fuel injection scheme served as a good demand for cars with such engines. This scheme was created according to the multipoint principle.
Due to the individual injectors in each cylinder, the fuel is distributed as evenly as possible in the cylinders. This design development, namely the release of engines with multipoint injection, was undertaken by Volkswagen. Due to which MPI engines subsequently appeared.
The appearance of such power plants constituted an alternative to carbureted engines. To better understand the MPI engine, you need to carefully analyze its competitive features.
The Modernity of Multi Point Injection Engines
There is no future for MPI engines, as it looked a few years ago, many even believed that the production of motors of this type was suspended. The radical development of automotive developments and technologies very quickly forces us not to remember yesterday's quality guidelines.
In fact, this is what happens with MPI engines, many in the industry claim that economy and environmental friendliness are obsolete.
But these conclusions are more true only for the European markets, and as for the Russian ones, then all this looks partly. Since the real potential of these units has not yet been fully revealed by domestic motorists.
Forward-thinking manufacturers keep this technology alive and are constantly introducing it to cars designed for Russian roads. For example, on Skoda Yeti or Volkswagen Polo. The most memorable were the representatives of the MPI system with engines, the volume of which was 1.4 or 1.6 liters.
Design features of the MPI engine
The absolute absence of a turbocharger is another significant feature of this system, along with a multipoint injection system. In the design of these engines, there is a conventional gasoline pump, which, under a pressure of 3 atmospheres, supplies fuel to the intake manifold for subsequent mixture formation and supply of a ready-made composition through the intake valve.
This scheme of work is very similar to the scheme of work carburetor engines. With one difference, that there is a separate nozzle on each cylinder.
Another unusual feature of the Multi Point Injection system of the engine is the presence of a water cooling circuit for the fuel mixture. This is due to the fact that there is a very high temperature in the area of the cylinder head, and the pressure of the incoming fuel is very low, because of this there is a high probability of a gas-air plug and, consequently, boiling.
Special Advantages of MPI
Before switching to a car with MPI, many motorists who are more or less familiar with this system will think very hard about getting a set of advantages due to which multipoint injection installations have earned their vocation in the world.
Simplicity of the device
This does not mean that such systems are simpler compared to carbureted models. If we compare the TSI model, which has a high-pressure fuel pump and turbochargers in its design, then naturally superiority is obvious. And the cost of the car will be lower and reduced operating costs and the possibility of self-repair.
Undemanding requests for fuel quality
It is not possible to guarantee the proper quality of fuel and oils everywhere and always, which is very typical for Russia. The use of low-octane gasolines below 92 does not affect the performance of MPI engines, as they are very unpretentious. The minimum mileage of cars without breakdowns, according to the developers, is 300,000 km, subject to the timely replacement of oil and filter elements.
The minimum value of the probability of overheating
The ignition timing is adjustable. The presence of a system of engine mounts, which is designed for the use of rubber mounts. Of course, this is not directly related to the engine, but it still matters for the performance of the engine and the comfort of the driver.
Since vibrations and various noises that occur when driving are damped due to the supports. An interesting feature is that the supports have automatic adjustment for various engine operating modes.
Characteristic Disadvantages of MPI
All the shortcomings of this engine are expressed precisely by its design features. The connection of fuel with air occurs in the channels, and not directly in the cylinders. Accordingly, there is a limitation intake system. This is expressed in a lack of power and rather weak torque.
Based on this, decent dynamics, sporty throttle response, and a hot drive are not obtained. In modern cars, the presence of eight valves is usually not enough, so all these characteristics increase. If to characterize this car with such a system, it will pass for a family and quiet transport.
That is why such cars have ceased to be in demand and fade into the background into the past. Why is this happening, i.e. the world made an assessment of the qualities of this system and decided that this was not enough for him, and the designers began to design more modern motors in terms of power. But no, there are unexpected surprises in the automotive industry.
The developers of Skoda, having developed the Russian version of the Yeti SUV for family use, in 2014 deliberately abandoned the turbocharged engine with a volume of 1.2 in favor of the MPI engine with a volume of 1.6 and a power of 110 hp.
According to the developers of the famous global concern, this engine has virtually nothing to do with old model 105 hp It is most suitable for TSI models, but it lacks direct injection and turbocharging.
Summarizing
The departure of engines from the world market with the MPI system is significantly affected by all of the above indicators. Today, many motorists prefer more powerful modern cars, the pace of which is steadily increasing.
The need to equip machines with stronger units significantly underestimates the demand for Multi Point Injection engines. Compared to them, this motor is rather weak. But it is still too early to write off the MPI engine completely, since the developers of the Skoda Yeti are trying to use it to the full on Russian roads.
To find out everything about the MPI engine, what it is, how it is arranged and by whom it was created, just read the material below. Such a power unit, which has the abbreviation MPI, which not all car owners are probably aware of, is German injection motor with a built-in multi-point system responsible for fuel injection. It was this feature of the power unit, which was an innovation just a few years ago, that served as the basis on which the name of this type of engine appeared - Multi Point Injection.
Experienced vehicle owners know that this complex device is provided for each cylinder. For the first time, Volkswagen employees were involved in the development of the scheme. The car concerns based in Wolfsburg used the MPI system everywhere, as it used to be the only injection system with fuel injection.
The invention, which was recently considered a sought-after novelty, today is not a unit that meets the latest economic and environmental standards that apply to everyone. The fact is that quite recently the device was discontinued, the last car that was equipped with an MPI engine was the second series Skoda Octavia. However, talented designers soon adapted the model of the power unit to new requirements, reviving the departed MPI engine. At the moment, most often you can find a 1.4-liter engine with a return of 80 liters. from. and 1.6 liters with a capacity of 105 liters. from.
Main characteristics
The MPI system, as mentioned earlier, stands for Multi Point Injection, which means the presence of multi-point injection. The power unit from is a non-turbo gasoline unit in which point injection operates during movement, which is distributed to all cylinders. This system implies the presence of cylinders, each of which is assigned a separate injector. Through such an injector, a metered supply of fuel occurs, which is carried out exclusively under pressure. The fuel passage is provided by a separate inlet channel.
The design of the power unit is such that it does not have a fuel rail, which serves as the basis for injection in TSI engines. Another feature of the MPI engine is the lack of direct injection, which goes to all cylinders (in comparison). The peculiarity and simplicity of the design of the unit determined the presence of the ignition timing function. In view of this circumstance, the throttle acquired ideal sensitivity relative to the gas pedal.
The complex mechanism is completed with an extraordinary water cooling system. The Volkswagen concern installed the MerCruiser system in its device, which stabilizes the correct performance of the power unit. With the help of such an element, the engine is freed from gas-air plugs.
The manufacturers of the modern MPI motor ideally thought out all the constituent elements, equipping the system with a special control hydraulic drive and a separate clutch with a built-in grease fitting. It is impossible to ignore the differentiated engine, which basically contains rubber supports that automatically adjust to the speed of movement, the speed of the power unit and the unevenness of the road surface.
All individual elements, assembled into a single design, have a beneficial effect on reducing vibration and noise from the motor. The engine has 4 cylinders and 8 valves. At the moment, units are produced with a volume of 1.4 liters with a return of 80 horses and 1.6 liters - with 105 liters. from.
The advantages of the power unit
If a person purchases a car with the MPI designation on the power unit, he needs to find out what MPI means. Like any other device, the motor has a number of certain advantages and disadvantages. First of all, let's consider the significant advantages of the unit, which during the operation made it possible to gather a millionth crowd of fans who still prefer to travel by vehicles equipped with MPI engines.
This type of motor is especially popular among Russians, since in the Russian Federation the standards that apply to the level of ecology have a number of concessions, unlike European standards. In Europe, there is not even close such a number of "antique" cars as, for example, domestic Russian "penny", mercilessly related to the environment. The thing is that fuel abroad is much cheaper.
Advantages of modern MPI devices:
- a design that does not look like a simple carburetor, but is not as complex as the TSI, equipped with many massive and "tricky" devices. Structurally, a simple unit is available in terms of cost, which is why it has the possibility of budget repairs;
- simple requirements for . The MPI unit installed in any car can be filled with simple 92nd gasoline with peace of mind;
- resistance to premature overheating.
An important advantage of such a unit is the reduction of noise and vibration, which manifests itself during movement.
Deficiencies in the operation of the motor
All the disadvantages that the MPI device has directly depend on the design features.
System disadvantages:
- while the car is moving, gasoline is mixed with air, this happens in the channels, and not in the cylinders, which negatively affects the limitation of the intake system;
- lack of power and lack of sufficient torque (directly related to the previous minus);
- the lack of excellent indicators regarding dynamics, drive and an important sporty throttle response.
All indicators are slightly aggravated by the number of valves provided, for modern machines 8 is just not enough. A car equipped with such a unit can be called quiet.
Conclusion
All of these indicators affect the departure of the MPI engine from the world market. The ever-growing pace of development of powerful maneuverable cars, which are preferred by most motorists, need to be equipped with more “strong” power units, compared with which the MPI engine is weak. However, it is too early to write off this engine, given the fact that on the Russian version of the Skoda Yeti (family SUV), manufacturers have replaced turbocharged engine volume 1.2 l power unit MPI with a volume of 1.6 liters with a return of 110 liters. from.
The developers of the updated MPI engine note its fundamental difference from its predecessor with a capacity of 105 hp. s., assuring that new unit belongs to the TSI family, with the only feature being the absence of turbocharging and direct fuel injection.
But there was one more, no less popular, which is installed on Volkswagen cars Group (now mainly on Skoda cars), this is an MPI engine. It should be noted that this engine is the oldest of the line. Volkswagen engines, however, it is the most trouble-free and practical of all units ...
MPI engine or Multi Point Injection (multipoint injection) - gasoline non-turbo engine using distributed multipoint fuel injection through injectors. One injector is used for each cylinder, there is no fuel rail as in TSI engines, and there is no fuel injection directly into the engine cylinders as in FSI and TFSI engines. The MPI engine has its own fuel injection structure. If I can put it roughly, one injector per cylinder, through a special inlet channel. It should be noted that it was he who replaced the carburetor engines.
Such an engine has the function of advancing the ignition process, which ensures high sensitivity of the gas pedal throttle.
The building has water cooling MerCruiser fuel mixture, which cools the fuel mixture to an acceptable temperature. Such cooling allows to increase the stability of the engine by getting rid of air - gas plugs.
It also has an advanced hydraulic control system. Coupling with a grease fitting. Engine Trim Limit System with memory (based on rubber mounts that automatically adjust to engine performance - reducing noise and vibration during operation).
It has an 8-valve gas distribution system, two valves per cylinder, one camshaft. Bright representatives of this family are 1.4 (80 hp) and 1.6 liter (105 hp) engines.
AdvantagesMPI
The engine is unpretentious, it may well run on 92 gasoline. It has a solid construction, as the manufacturer himself assures, the minimum mileage without repair is 300,000 kilometers, with timely oil and filter changes. Not expensive and not complicated repairs, due to a simple device.
disadvantagesMPI
Due to the fact that the fuel mixture is mixed in special intake passages before entering the cylinders, such engines have limited intake system capabilities. This affects the power and. They can not be called "dynamic" and powerful. Most likely, they are designed for a leisurely ride. The presence of eight valves, and most of these engines have eight valve timing systems, also indicates a loss of power.
Due to their old design, MPI engines are gradually being phased out, latest models on which this family of engines was installed, there were cars brand SKODA Octavia second generation. However, the third generation of OCTAVIA vehicles has more modern and advanced FSI engines And .
I think it became a little clear what this engine is.
An article about the MPI engine - features of the motor, its operation, advantages and disadvantages. At the end of the article - a video about the analysis of the MPI motor.
The content of the article:
At the end of the last century, MPI (Multi-Point-Injection) engines with multipoint fuel injection replaced carburetors and were considered the most advanced technology in engine building. This technology was developed by the Volkswagen Group. The first engine with the MPI system was installed on the Volkswagen Polo, and later they began to equip the Golf and Jetta models.
For the past few years, MPI motors have only been installed on Skoda models, and the last Skoda with MPI technology was the Skoda Octavia 2-series (the 3-series has already been equipped with more modern motors– TSI and FSI).
Today, most experienced car owners with experience consider MPI engines to be outdated and almost rare. The same opinion is shared by specialists from Volkswagen, considering given type the engine no longer meets modern European requirements for efficiency and environmental friendliness.
However, despite this, MPI motors still have a reputation for being the most reliable and practical of all injection units. In addition, MPI technology turned out to be in demand in Russia, where in 2015, Volkswagen launched a production line for assembling MPI motors of the EA211 series at the Kaluga plant. This became possible due to the lower requirements in Russia for the environmental friendliness of engines compared to Europe.
Each cylinder has a separate injector with a nozzle!
The main feature of injection MPI engines with multipoint fuel injection is that each cylinder has its own separate injector with a nozzle. With the help of injectors, a metered injection of fuel is carried out into each individual cylinder, with spraying through the nozzles. This method allows you to evenly distribute the fuel mixture over all cylinders. At the same time, unlike the TSI engine, the MPI design does not have a fuel rail and there is no direct fuel injection into the cylinder, which is found in the FSI and TFSI systems.
Important! Motors with MPI technology work with ignition advance, which makes the gas pedal very sensitive to impact.
No turbocharger
Another significant feature of MPI engines is the complete absence of a turbocharger in their design with a multi-point injection system. Instead, MPI motors are equipped with a conventional gasoline pump with a pressure of 3 atm. The order of operation of the MPI system is as follows:
- from the gas tank, fuel is pumped by the gasoline pump into the injector;
- the electronic injection control unit sends a signal to the injector, and fuel is sprayed under pressure through the nozzle to the cylinder intake valve.
- devices for delivering fuel to injectors;
- ignition block;
- air mass dosing device;
- device for adjusting the toxicity of exhaust gases.
Water cooling circuit
The water cooling circuit in MPI engines is designed to cool the combustible mixture. During operation of the unit, the cylinder head is very hot, and the fuel is supplied under low pressure. As a result, there is a great danger of a gas-air lock, which can lead to overheating with boiling. The presence of a water cooling circuit for the combustible mixture prevents the occurrence of such overheating.
The fuel-air mixture for MPI engines must have the following quality characteristics:
- Gaseousness. For efficient combustion of the fuel-air mixture, the gasoline must completely evaporate before it ignites.
- Homogeneity (uniformity). The evaporated fuel must mix well with the oxygen contained in the air mass. Incomplete fuel mixing in oxygen rich areas increases the risk of detonation. In places with increased enrichment, the fuel does not completely burn out, which leads to a decrease in engine efficiency.
- The volume of injected fuel must be proportionately sufficient to mix with the air pumped into the cylinder. For example, for a more complete combustion of the fuel-air mixture, it will be necessary to mix 1 kg of gasoline with 14.7 kg of air mass. With an increase or decrease in the amount of air, either depletion or re-enrichment of the fuel mixture will occur, respectively. However, it should be remembered that the narrowness of the range of proportional changes in the composition of the mixture leads to a small efficiency of the gasoline MPI engine, for example, compared to the diesel ICE cycle.
Hydraulic control mechanism
MPI engines are equipped with a special hydraulic drive control mechanism, with a clutch with a grease fitting to limit trims. In addition, the specified control mechanism is equipped with special soft supports, which are automatically adjusted to the operating mode of the engine and reduce noise with vibration.
MPI motors have the following advantages:
- Proportional accuracy when mixing fuel with air. Fuel is injected through injectors directly onto the cylinder intake valves, which eliminates the possibility of uneven filling. The timing of fuel injection through the injector is precisely determined by a controlled pulse. The amount of incoming fuel will depend on the duration of the open state of the nozzle.
Generally, fuel system controlled by an ECU (electronic control unit) or, more simply, on-board computer. The control unit (ECU) is able to calculate (based on information from the sensors) not only the moment of injection, but also the required amount of fuel to prepare a high-quality fuel-air mixture.
- Minimum loss during evaporation of gasoline. The close location of the nozzles to the intake valves eliminates the need for a significant re-enrichment of the combustible mixture to warm up the engine. Also, the proximity of the injectors to the valves allows the fuel to remain in a liquid state longer after injection, which leads to a decrease in heat in the combustion chamber. With an increase in the degree of resistance to detonation, it is possible to change the compression ratio with increasing engine power.
- Injection stroke with increased pressure. Increasing the injection pressure makes it possible to turn the fuel into a fine dispersion, which significantly improves the combustion of the fuel-air mixture.
- Thanks to the ability of the ECU (Engine-ECU) to read certain data (speed, speed, actual and recommended load, etc.), an accurate calculation of the injection time and the amount of gasoline occurs. This allows MPI engines to produce optimal power with relatively low fuel consumption.
In addition, the simplicity of the engine design allows you to save on its repair. Also, the design of the MPI engine compares favorably with more complex designs. TSI engines, which have rather complex and expensive high-pressure pumps and turbochargers to repair. Plus, the MPI engine is smaller and less likely to overheat.
Advantage of MPI in comparison with carburettor and mono-injector
The advantage of the MPI system is due to the disadvantages of carburetors and mono-injectors. Simply put, MPI technology was developed to overcome the shortcomings of carburetor and mono-injection technologies that did not allow for accurate metering of fuel supply and reduce fuel loss during engine warm-up.
Technologically, fuel was supplied through a carburetor (or mono-injector) directly to the intake manifold, which led to increased consumption fuel and higher emissions. During a cold start of the engine, most of the incoming fuel condensed (settled) on an unheated manifold, as a result of which the fuel-air mixture had to be re-enriched.
Disadvantages of MPI motors
- Slow start and acceleration. According to experienced drivers, MPI motors have less dynamics. And indeed it is. The loss of dynamism occurs during the mixing of fuel with air directly in the exhaust channels, before it is fed into the cylinders. The fact that MPI motors are not designed for quick start and acceleration is also indicated by the presence of an 8-valve system with a timing kit.
- Little economy. MPI engines are inferior in terms of fuel economy to TSI engines with supercharging and direct fuel supply to the cylinder.
Judging by the same reviews on the Internet, the problem with cold start knocking was less affected by the CWVA engine modification (with the same volume of 1.6 liters). But the cost of eliminating the knock was an even greater overspending of oil. The fact is that the designers from Volkswagen decided to compensate for the increase in the load on the CPG during a cold start with new oil scraper rings leaving a thicker layer of oil on the cylinder walls.
Motors with MPI technology are perfect for use in Russian conditions.
- They are not demanding on fuel quality, which is important for the Russian fuel market. After all, until now, the fuel at many Russian gas stations does not differ high quality. But MPI engines are able to work well and for a long time even on gasoline with an exorbitant sulfur content.
- Simple and reliable, with additional protection against mechanical loads, the design of the MPI engine is also relevant for Russian roads, most of which (as well as fuel) are not of high quality.
- MPI engines comply with Russian environmental emission standards, unlike Europe, where environmental requirements for engines are much higher.
Video about disassembling the MPI motor:
