When choosing a new or used car, buyers pay Special attention which engine is located in engine compartment, look at its characteristics, strengths and weaknesses, as well as possible faults.

All this allows you to understand how correct and rational the purchase of a particular vehicle will be. In the history of every car company, there are both ups and downs regarding the creation of power plants. Some motors become exemplary, while others are more likely to be forgotten.

One frequently discussed engine is the Korean CRDI. The development belongs to the engineers. Here we are talking about a diesel power unit equipped with a direct fuel injection system. This motor is installed only on Korean cars different models. But if we talk purely about design features, then similar internal combustion engines are found on the machines of European companies.

Device Features

Motorists and potential buyers of Korean cars are naturally interested in the question of what CRDI engines are and what distinctive features they have. Let's start simple. Namely, decryption.

Some already know what this abbreviation CRDI stands for. This is the engine marking for Common Rail Direct Injection. The first two words make it clear that one common fuel line is used, which is used in Korean diesel engines and their analogues.

Sometimes such a highway is called nothing more than a rail. At the same time, the fuel inside this line is not only under constant, but also under sufficiently high pressure. The pressure itself is formed due to the operation of the high-pressure fuel pump, familiar to many by the abbreviation high-pressure fuel pump.

But when compared with classical systems of high-pressure pumps, here the opening of the nozzles does not occur under the influence of excessive pressure parameters. This function is performed by solenoids controlled by the ECU.

The pressure in the CRDI does not depend on the speed of rotation. crankshaft or the amount of fuel itself. The driver can control and somehow influence solely the amount of fuel that is injected into the system. As for the advance angle and diesel fuel injection pressure, this task is fully controlled and regulated by the control unit, that is, the ECU. Such a scheme of work makes it possible to separate the creation of working pressure and the process of fuel injection itself.

This allows more than one injection headlight to be used in one cycle. Initially, CRDI type motors were only two-phase. But already now, on certain power plants, there can be about 9 phases for only 1 cycle.

We can say that the type of Korean CRDI and all existing full-fledged analogues is as follows. Here, fuel is supplied to the injection nozzles through the use of a common tank. All diesel fuel comes from there. In this case, the fuel itself is under the influence of high pressure.

This allows you to significantly distinguish CRDI from classic diesel power units, which use fuel pump and cam drive.

Considering everything design features, the process of operation of the considered motor can be described as follows:

• when the driver turns the key in the ignition lock, the process of fuel injection takes place in the fuel rail due to the operation of a special pump installed in the design;
• while the rail acts as this very reservoir or container with fuel;
• in the rail, the fuel pumped by the pump is constantly under pressure, which is necessary for injection;
• then from the rail it is supplied under pressure to the injector nozzles through the corresponding pipelines.

Such engineering solutions allowed the CRDI type engine to receive a number of objective advantages.

At the same time, we must not forget that the motor also has certain disadvantages and problems that may arise during operation. Although this is typical for any engine.

Existing analogues

In addition, companies producing similar power plants use their own marking options. It is worth highlighting a few really worthy analogues:

1. FIAT offers in its models a diesel power unit, in many ways reminiscent of the Korean CRDI. Only the Italian stable labels its engine as CDTI.
2. A similar motor is present in the arsenal of the leading American. On their machines are offered diesel units with direct injection, which are called TDCI.
3. Another American auto giant, General Motors, equips its cars with diesel engines. They are identified by the abbreviations VCDI or CDTI, as is the case with FIAT.
4. And, of course, it should be noted Volkswagen, which has a range of TDI engines.

Some other companies also have analogues of the Korean CDRI, but they are not as popular and widespread as the considered analogues.

All presented motors are in many ways similar to each other and they are united by one common concept. However, there are some structural differences between them. But if we take into account only the basis, then all these are diesel power plants equipped with a diesel fuel direct injection system.

Potential problems and malfunctions

Compared to Western countries, the demand for diesel power plants in Russia and the CIS countries is much lower. There are certain objective and sometimes subjective reasons for this.

CRDI engines have certain shortcomings that can lead to malfunctions.

There are several examples and explanations for this.

1. CRDI is considered more reliable than a classic diesel engine, which uses a high pressure pump. At the same time, all details require a high level of precision. Plus, the motor contains a large number of electronics. Therefore, increased reliability is only a conditional concept.
2. Motors of this type are very dependent on the quality diesel fuel, which in our conditions provokes the occurrence of a whole kind of malfunctions and problems. The quality of diesel fuel at our filling stations leaves much to be desired. Hence the corresponding problems during operation.
3. Rapid wear . When planning to operate a vehicle with a CRDI engine, be prepared to change the fuel filter. The reason for this is the same low quality of diesel fuel. Impurities and all sorts of contaminants quickly clog the filter element. If it is not changed on time, it can lead to serious negative consequences.
4. The dependence of performance on electronics. Although in many ways electronics can improve engine performance, automate many processes and ensure optimal performance, any breakdown can minimize all the advantages of such diesel engines.
5. Problems arising during the period of severe frosts. CRDIs are not particularly friendly with Russian cold weather, which is why various kinds of troubles and malfunctions often occur in winter. It is connected mainly with bad fuel and the inability of diesel fuel to function normally in the engine system. This can cause overheating, failure of some elements and the final costly repair.

In order to prevent the occurrence of certain problems, you should strictly adhere to the rules of operation, follow the recommendations for maintenance, change consumables in a timely manner.

But still, the main factor in the long, trouble-free and trouble-free service of CRDI can be safely considered the quality of the diesel fuel used. If you refuel at really good and proven gas stations, where the quality of the fuel is at a decent level, there should not be serious problems with this diesel engine equipped with a direct injection system.

Advantages

If we compare a diesel power unit of the CRDI type with the classic versions of engines running on diesel fuel, then an internal combustion engine with a direct injection system has a fairly wide list of advantages.

Among the most significant advantages are the following:

• high rates of economy. The created high pressure, which will remain in the fuel system on a permanent basis, makes it possible to redirect diesel fuel much more efficiently for further engine operation. The injection system used allows you to burn fuel to the maximum extent. This automatically helps to reduce fuel consumption for the engine to perform its functions, that is, to give the car acceleration. Although diesel engines are already considered economical, CRDI managed to take another big step forward;
• excellent environmental friendliness. This advantage follows from the previous motor feature presented. Since CRDI can burn fuel as much as possible and consumes less diesel, this reduces the total toxicity of the resulting exhaust. This is especially noticeable when high-quality fuel is poured into the tank;
• constant pressure system. In diesel systems, where provided direct injection fuel, the pressure does not depend on how fast an element such as a crankshaft rotates. Also, it does not depend on the volume of fuel or other parameters. This is because fuel is constantly pumped in the fuel rail, that is, it is under constant pressure. This helps to increase the efficiency of the motor;
• fuel is supplied by work electronic block, which is called EDC. The needle in the fuel injection nozzle rises due to the fact that the electronic unit gives the appropriate command and it is implemented through a controlled solenoid. This eliminates the need for the fuel itself to influence the process of lifting the nozzle needle;
• Availability electronic control. CRDI engines outperform competitors due to the fact that the amount of fuel supplied, the injection pressure and the same injection advance angle are determined and regulated electronically through the use of a control unit. Thus, the system can automatically select optimal parameters and set them during the operation of the engine in different conditions and modes of operation. At the software level, here you can set the required injection pressure parameters, which depend on the speed of movement, the load on the car and other nuances;
• no high noise level. Among all its competitors, CRDI engines can be considered almost silent. Yes, they cannot work completely silently, but the noise effect created is negligible. This is due to the fact that the system uses the so-called phased injection. On certain modern motors, the number of phases reaches 9. This feature affects not only the improvement speed characteristics motor vehicle. It also helps to reduce the noise level during the operation of the diesel power plant;
• fuel is under high pressure. It is extremely difficult to achieve high pressure in standard diesel engines. Usually this parameter does not exceed 300 kg/cm2. If we talk about CRDI, then such a system, due to the operation of direct injection, reaches parameters of more than 2000 kg / cm2.

As you can clearly see, CRDI has a really long list of objective merits. It is they who allow these engines to be in many ways a priority choice for the buyer when purchasing a car with a diesel engine. power plant.

But before drawing final conclusions about diesel engines with a diesel fuel direct injection system, you should first study their characteristic shortcomings.

Flaws

In fact, the technology on which the CRDI diesel powertrain and its analogues are based is significantly superior to standard diesel engines. But also the system turned out to be noticeably more complicated, from which follows a list of certain shortcomings.

1. High level of sensitivity in relation to the quality of the filled diesel fuel. If in Europe this disadvantage does not manifest itself strongly, then in Russia and the CIS countries such sensitivity makes itself felt almost immediately after the start of operation. The engine uses a complex system and a multi-level design. If the fuel pump, injectors and any other elements responsible for supplying and processing fuel get debris and various kinds of pollution, this can potentially cause serious problems and malfunctions. Therefore, such contaminants must not be allowed to be contained in the fuel. This provides for the mandatory need to use exclusively high-quality fuel. Since it is not so easy to find gas stations with clean diesel fuel in Russia that actually meet all European norms and standards, car owners have to choose gas stations with particular care. To minimize the risks, you should periodically check the condition of the filters and change them in time.
2. Relatively high cost. If we compare it with conventional traditional diesel engines, then engines implemented using CRDI technology will initially cost the buyer more. This is due to the complexity of the design and diesel fuel direct injection system, which increases the manufacturing costs. This also entails an increase in the cost of the motor during its implementation. In order for CRDI to work correctly and correctly, it is equipped with special sensors, a special setting is preliminarily carried out, and the electronic unit is programmed. This entire list of mandatory activities that are carried out in the process of assembling and directly preparing the engine for operation requires resources from automakers. Therefore, companies simply cannot sell CRDI at a price similar to standard diesel engines. This will be a direct loss in which no one is interested.
3. Difficulty in repair and high cost of maintenance. And this disadvantage is directly related to the fact that CRDI with a diesel direct injection system is much more complicated in design and construction. Because of this, the process of repair and maintenance becomes more complicated, more resources are required for complex diagnostics. Since now such motors can be called conditionally new developments that have entered the market relatively recently, not every car service is ready to take on the maintenance and repair of such a power unit. Most masters simply lack the experience and knowledge of the complex structure of such an engine. They are unable to provide good service.
4. The difficulty of finding masters. A disadvantage arising from all the previous disadvantages, which is quite relevant for motorists from Russia and the CIS countries. All the same complex structure of the system provokes such a problem as a shortage of personnel capable of servicing and repairing CRDI engines with high quality. The best solution is to contact certified and official service centers, directly associated with companies that sell cars with the appropriate power plants. But this automatically raises the cost of repair and maintenance of the machine, guarantee period which has already expired.
5. Low maintainability. Unlike the same classic diesel engines, where a huge number of individual parts are subject to repair, restoration and replacement, CRDI cannot boast of such characteristics. The maintainability of the diesel engines under consideration with a direct fuel injection system and fuel supply under pressure is rather insignificant. A large number of elements cannot be restored if they fail. The only way to fix this problem is by replacing it. Moreover, some components change exclusively modularly. This automatically significantly increases the costs associated with the maintenance and maintenance of such an engine. Instead of buying one small part and changing it, you have to purchase a whole module.

But here it is necessary to be extremely objective. All the shortcomings considered are rather conditional, since they arise from only one nuance. And we are talking about increased sensitivity to the quality of the fuel used. This has created a misconception that CRDI engines have a low level of reliability. Such a statement is completely untrue.

Enough to fill in fuel tank good diesel fuel, and all these problems will not concern the car owner at all. Yes, there are a number of other factors that can cause breakdowns and rapid wear. But they are all associated with an aggressive driving style and negligent attitude towards the car.

It is the low quality of diesel fuel that leads to more than 90% of malfunctions with CRDI engines. In fact, it is enough to solve one problem, and the attitude towards this motor will change.

Buying a car with a CRDI type power plant is a personal matter for everyone. You should carefully study all the features of the motor, consider its strengths and weaknesses, on the basis of which you should already make the appropriate correct decision.

How long the engine will last and how much you will be able to experience all the objective advantages of CRDI depends precisely on the attitude of the driver to his vehicle. Adhering to the manufacturer's recommendations for timely maintenance and replacement Supplies, as well as trying to visit proven gas stations, this motor will be able to show all its best qualities. And then there will be no talk of any complex and expensive repairs.

CRDIs are truly the next step in the development of high performance and high efficiency diesel engines that offer superior performance. technical specifications with excellent economic performance. But objectively, domestic diesel fuel is not yet ready for such engines.

Modern cars are increasingly equipped with diesel engines. This is especially true for medium and large cars. But the subcompact class is increasingly equipped with heavy fuel engines.

The dominant version of the diesel engine in recent years is the CRDI system (the abbreviation stands for Common Rail Direct Injection). What is a CRD engine, what are its advantages and disadvantages, why is it better than previous systems, we will talk about this in this article.

Common Rail in the name of such engines tells us about the presence of one common fuel line. Indeed, CRDI engines use such a line, sometimes called a rail, in which the fuel is under constant, high pressure. This pressure provides familiar to motorists from previous diesel systems, high pressure fuel pump - injection pump. But unlike the classic injection pump system, the nozzles do not open under the influence of excess pressure, but with the help of special solenoids, which are controlled by the EDC unit. In Common Rail Direct Injection, the pressure in the system does not depend on either the crankshaft speed or the amount of fuel itself. Here, the driver can only influence the amount of fuel that is injected, but the advance angle and the pressure with which diesel fuel is injected are all regulated by the engine's electronic control unit. This solution allows you to separate the injection of working pressure and the actual injection. And this, in turn, makes it possible to use more than one injection phase in one cycle. At first, CRDIs were produced in two-phase, but now some engines use up to nine injection phases per cycle.

Benefits of CRDI

There are a lot of advantages of Common Rail Direct Injection, we will list and analyze only the most important ones.

• profitability;
• power;
• reduction of harmful emissions;
• longer service life, in comparison with the previous system;
• increased responsiveness and acceptance;
• smoother and quieter operation;

By creating and maintaining a constant high pressure, the fuel is atomized more efficiently, which has a very positive effect on its combustion. And this is power, and efficiency, and reduced emissions.

Thanks to the use of multi-phase injection, it is possible to achieve really soft and smooth engine operation throughout the entire rev range. Which positively affects both the actual ride and the comfort of the driver and passengers.

One of the main disadvantages of the classic injection pump is the peculiar waves that occur during the operation of the motor. Such pressure drops had a very negative effect on the service life of the system. In CRDI engines, this problem is absent, which allows them to work much longer. All these advantages have made CRDI diesels popular not only among motorists, the same or similar system is used in new models of locomotives and in shipbuilding.

Possible problems with CRDI

Nevertheless, diesel cars in our country do not enjoy such love and popularity as in the West. There are reasons for this, and such a system also has its drawbacks.

For example, although Common Rail Direct Injection is more reliable than conventional injection pump systems, the highest accuracy of all parts and elements, as well as the presence of many electronic components, make it not so reliable. The complication of the system almost always leads to a decrease in its reliability. This is especially felt by domestic motorists. After all the most important parameter for long and stable operation of the CRDI engine, is the quality of the fuel. And at domestic gas stations, this often causes serious problems. So, simply and imperceptibly, bad diesel fuel kills even the most reliable and high-quality engines.

The high cost of repairing or replacing elements of a CRDI engine is a fact also well known to the owners of such machines. The cost of repairing modern diesel engines is orders of magnitude higher than the cost of the same work for engines running on gasoline. In addition, to carry out repairs in such motors, special equipment and highly qualified professionals are needed. And if there seems to be not so many problems with the first one, then an experienced diesel engine repair specialist, especially in the provinces, is a real treasure.

And of course, climate features, and more specifically low temperatures in winter, they can also seriously interfere with the normal operation of a heavy fuel engine, regardless of the system of this engine. And we have to install fuel heaters, autonomous stoves and other equipment designed to reduce the negative impact of frost on diesel fuel. Various antigels and other additives are also used for this purpose.

Generally, correct selection auxiliary means allows you to eliminate most situations when in cold weather diesel car refuses to start. But with gasoline engines such problems do not arise at all. So people are trying not to get involved with diesel engines without unnecessary need. However, every year there are more and more of them on our streets and roads. There are specialists who are able to repair CRDI and other types of diesel engines with high quality, the quality of diesel fuel is improving, and experience in operating such systems is emerging and expanding. All this contributes to an increase in the number of cars running on heavy fuel.

As a result, we can say that Common Rail Direct Injection today is the best way systems for a diesel engine and with a careful attitude towards it, such a motor will fully show all its advantages and positive qualities. Meanwhile, such motors have a number of disadvantages that make you think carefully before purchasing a car equipped with a CRDI engine.

The car system with the designation CRDI, also called Common Rail, has certain pluses and some minuses. Today it is installed on enough a wide range automotive engines, it is characterized by certain characteristic differences in its modifications.

The system, designated as CRDI, was developed as the main system for powering the engine, but even now many car owners still consider it something too exotic, and therefore not reliable. In fact, the situation is somewhat different, and CRDI is used on a large number of various models auto.

For Daimler concern cars, such a system is characterized by the designation CDI, CRD, on Fiat concern cars this abbreviation will be JTD, TTiD, DDiS, Ecotec CDTi, on Ford it is TDCi, Kia and Hyundai - CRDi or Common Rail Direct Injection, on Volkswagen Group - TDI .

In addition to the automotive industry, power units, which use this solution, are very actively used in shipbuilding processes and on railway locomotives.

When translated from English, "common rail" can be translated as "common rail" or "common rail".

In accordance with the name, the principle of operation of such a system is based on the process of supplying fuel to the injectors, using a common accumulator in which a sufficiently dense fuel pressure is created before it is injected. That is, specifically for pumping high fuel pressure, a common ramp has been developed (it is also a common rail). The creation of high pressure during the supply of fuel and its support throughout the fuel system occurs regardless of the speed of rotation of the crankshaft in the unit or the actual amount of working fuel that is injected.

This is the main difference from the standard diesel-type system with high pressure pump, as well as a cam-type drive, which is characterized by low pressure during fuel supply. The injection process is carried out by injectors under the control of the EDC controller unit, using special magnetic solenoids that are built directly into the injectors. Their activation comes from the control unit.

That is, from the very initial revolutions of the crankshaft in the engine, the fuel is injected into the common rail system, where it is under fairly high pressure. From now on, it is always ready for injection. The features of the subsequent operation of the injector system and the entire mechanism as a whole also depend on the actions of the driver, which is calculated and implemented using an electronic control unit.

The processes of forcing and maintaining pressure, as well as the injection itself, are completely separated, injection can be performed both two-phase and multi-phase (up to 9 phases), depending on the nature of the vehicle’s operating mode at the moment, load or high-speed.

Benefits of using Common Rail systems on all modern cars we can name, first of all, the ability to meet the strict requirements in terms of efficiency and environmental friendliness of the engine, which are steadily increasing every year.

In addition to reducing emissions, the system also helps achieve significant savings through finer fuel atomization. This allows you to simultaneously reduce the amount of harmful emissions and noise levels, as well as increase economy and engine power, due to more efficient almost complete combustion of fuel. By means of a high and constant pressure, during the injection process, it is also possible to achieve precise dosing, without any pressure waves.

The CRDi system, due to its stability in maintaining a constant high pressure in the fuel supply line, eliminates the “wave” pressure surges that previously led to the destruction of the fuel lines. Thanks to this, the pressure can now be increased many times (up to 2,000 bar), and at the same time, all the work that takes place inside the nozzle will not have a destructive effect.

Among certain disadvantages of the CRDi system, several increased requirements for the purity and quality of diesel fuel can be noted. Due to the high precision of the system elements, as well as the constant high pressure, even the smallest foreign particles can damage the system components.

CRDi (Common Rail Direct Injection), also known to motorists as common rail is a modern common rail fuel system that is used in diesel engines. The operation of the system is based on the supply of fuel from a common battery to the injectors. It was developed by Bosch.

Some motorists mistakenly believe that this system is rare and even exotic. However, such a power system is widely used by many well-known manufacturers, only it is called in most cases differently:

• Volkswagen: TDI Fiat: CDTi, DdiS, TtiD or JTD;
• Daimler: CRD, CDI;
• Hyundai and Kia: CRDi;
• General Motors: CDTi, VCDi.

Also, engines with CRDi are quite actively used in shipbuilding and on railway locomotives. The meaning of the term CRDi can be translated as common rail direct fuel injection.

The CRDi system consists of:

• high pressure fuel pump
• fuel metering valve
• fuel pressure regulator or control valve
• fuel rail and injectors.

All elements are connected by fuel lines.

In the CRDi system, the pump pumps fuel at a sufficiently high pressure, which can reach up to 300 MPa, depending on the engine's operating mode, into the total fuel line with a significant volume, that is, in the battery. It uses direct fuel injection.

The CRDi system is used in diesel engines, but in design it has many similarities with gasoline engines. The main difference is the principle of fuel ignition. The key feature of the CRDi system is the independence of injection processes from the angle of rotation of the crankshaft, which subsequently makes it possible to achieve high injection pressure in partial modes.

Injection control made it possible to significantly reduce toxicity exhaust gases and reduce diesel engine noise. The CRDi scheme fully complies with Euro 5 environmental standards.

CRDi or Common Rail is an engine power system that many drivers mistakenly consider exotic and rare. Many people use this power system in their cars. well-known manufacturers, only it is called differently:

• Volkswagen: TDI;
• Fiat: CDTi, TtiD, DdiS, JTD;
• Daimler: CRD, CDI;
• Hyundai and Kia: CRDi;
• General Motors: CDTi, VCDi

CRDi engines are also widely used in railway locomotives and shipbuilding.

CRDi (Common Rail Direct Injection) can be translated (decoded) as direct fuel injection along a common line.

The essence of the operation of this system lies in the technology of supplying fuel from a common high-pressure accumulator ( fuel rail) to the injectors. The pressure in the fuel system does not depend on the amount of fuel injected and the speed of the crankshaft. The injection command for the injectors is issued by the EDC unit controller. This procedure is carried out thanks to the magnetic solenoids installed in the nozzles.

Principle of operation:

• Fuel ready for injection is in the rail under high pressure.
• It is pumped into the ramp by a special pump immediately after the start of the first revolutions.
• Then the fuel through the fuel line begins to be supplied to the injectors under total pressure.
• This is one of the main differences between the CRDi system and engines with a classic injection pump - the nozzle needle is raised by a solenoid, and not by fuel pressure.
• The cyclic fuel supply (quantity) is set by the driver himself, and the injection pressure and advance angle are set by the program embedded in the ECU (control unit).

The fuel injection process and the formation of pressure in the CRDi system are separated. From here, it becomes possible to create two-phase and multi-phase injection. In addition, this fact allows you to use several injection phases in one working cycle at once. In the initial versions of the system, double injection was used. In modern CRDi, up to nine phases are used.

The main advantages of the Common Rail system compared to conventional "diesels":

1. Establish stringent requirements for engines in terms of environmental friendliness and efficiency. These requirements are getting tougher every year. Diesel engines with outdated injection systems are not able to meet the requirements for protecting the environment from harmful emissions.
2. Due to the increased fuel pressure, the CRDi system provides significant fuel savings. The higher the fuel pressure in the combustion chamber, the finer the spray will be. Thanks to this, a more complete and efficient combustion of the mixture occurs against the background of lower emissions of harmful substances and an increase in power.
3. In addition, the constant high pressure in the line ensures accurate fuel dosing throughout the entire duration of the injection. With a classic injection pump, it is simply impossible to create increased pressure in the fuel system.
4. When changes in fuel consumption occur in the channels from the injection pump to the injectors, so-called “waves” of pressure appear, which “pulsate” along the fuel line. This "wave hydraulic pressure" destroys fuel system. For this reason, there are no injection pumps in which the pressure on the nozzles is more than 300 bar. In turn, the Common Rail system generates pressure up to 2000 bar. Significant destructive vibrations do not occur, and all work is carried out inside the nozzle.