Not everyone knows what TSI is and how this abbreviation stands for. We will talk about this today.
What is TSI
The TSI engine is a petrol-powered unit characterized by a "twin turbo" system. The translation of the abbreviation TSI is as follows - an engine with a turbocharger and fuel injection in layers.
A distinctive feature of the TSI design is the placement of a turbocharger on one side and a system responsible for mechanical compression on the other. The use of energy from exhaust gases allows you to increase the power of a conventional turbo engine. This is possible due to the fact that the exhaust gases start the turbine wheel and forcefully pump and compress the air thanks to the drive system. Such a system shows greater efficiency than traditional ones.
What is improved in TSI engines
Recognized by experts and consumers, as evidenced by numerous awards. This system for three years (from 2006 to 2008) became the owner of the "Engine of the Year" award at the "Engine of the year" competition.
Using the concept of minimization, the essence of which is that a smaller engine with a small consumption of gasoline produces the most power. The reduction in the working volume made it possible to increase the efficiency, while reducing friction losses. The small volume facilitates the engine and the car as a whole. Such technological solutions have become an integral part of TSI.
Video showing how the TSI engine works:
Combining drive and economy. The initial goal of the developers was to create economical engines with high power and reduced CO 2 emissions.
Large rev range. TSI systems are tuned so that when the crankshaft rotates at a frequency ranging from one and a half thousand to 1750 revolutions per minute, then the torque remains at its highest, which has a good effect on how much gasoline is saved when the car is running, and on the power of the car. As a result, the driver receives maximum power at a large rev interval. TSI engines go well with transmissions that have gear ratios that are much larger, which has a positive effect on.
Optimization of mixture formation, which was achieved due to the specially developed design of the high pressure nozzle with 6 holes. The injection system is tuned in such a way that it provides greater efficiency in the combustion process of gasoline.
Intercooling provides more dynamics. Another distinguishing feature of the unit is the presence of an intercooler of liquids, which has a system in which it circulates independently. This cooling reduces the volume of air that is injected, due to which the boost pressure rises faster. As a result, due to small delays in the turbo effect and the level of optimal filling of the combustion chamber, an increase in dynamics is achieved. TSI with a declared power of 90 kW without an auxiliary compressor does not have a turbo lag. Already when reaching the mark of 1500 rpm, you can get the highest torque data of 200 Nm.
Supercharging in TSI
Turbocharging and fuel injection. The TSI system uses a special technology that has made it possible to obtain the highest level of torque and the highest power for a car, despite the fact that the engine has a rather small volume: fuel injection together with turbocharging or combined supercharging with a turbocharger and compressor. In this design, the combustion of fuel is more efficient, due to which the power of the TSI exceeds that of traditional naturally aspirated engines.
A turbocharger combined with a compressor gives a good effect. The use of another compressor helped to smooth out the effect of turbo-lag, which occurs due to the fact that the turbocharger creates a sufficiently high boost pressure when the rev range is higher.
boost pressure readings. The Roots mechanical compressor is driven by a belt drive from the crankshaft. In this case, the level of force with which boost occurs begins at the smallest range with which the revolutions occur. This approach provides high traction characteristics and torque indicators in a large rev interval.
Dual supercharging, which is used in engines of this type, an efficient injection system, together with the highest pressure indicators with which fuel is injected, and the use of six-jet nozzles, make it possible to achieve gasoline savings for TSI engines, which is spent. Today, Volkswagen-built cars from the Golf plus series, the Golf and Jetta range, the Touran and the new models already have a turbocharged engine.
Revolutionary innovative technology
Today, Volkswagen is the only manufacturer that serially installs engines of this type, equipped with double supercharging in combination with staged injection, in cars of its own production. The placement of the compressor and turbocharger makes the pressure force with which boost occurs more. That is, an engine with a displacement of 1.4 liters is able to develop up to 125 kW (or 170 hp), which is a record in the automotive industry among four-cylinder engines.
Fuel savings due to reduced weight. The new TSI engine models, thanks to a number of improvements, weigh 14 kg less than the same type of engines equipped with a dual-charging system. Innovations include: design optimization of the block head and lighter weight of its cover, weight reduction of 304 grams of all camshafts.
Video about the operation of a turbocharged internal combustion engine:
It is quite logical that the complexity of the design and improvements in engines also affected. However, a slight rise in price is fully compensated by increased power indicators and a decrease in the amount of fuel consumed.
TSI engine ( Turbo Stratified Injection, literally - turbocharging and layered injection) combines the latest achievements in design thought - direct fuel injection and turbocharging.
The Volkswagen concern has developed and offers on its cars a line of TSI engines that differ in design, engine size, and power performance. In the design of TSI engines, the manufacturer has implemented two approaches: dual supercharging and simple turbocharging.
The abbreviation TSI is a patented trademark of the Volkswagen Group.
Dual supercharging is carried out depending on the needs of the engine by two devices: a mechanical supercharger and a turbocharger. The combined use of these devices makes it possible to realize the rated torque in a wide range of engine speeds.
The engine design uses a mechanical supercharger of the Roots type. It consists of two rotors of a certain shape, placed in a housing. The rotors rotate in opposite directions, which achieves air intake on one side, compression and discharge on the other. The mechanical supercharger has a belt drive from the crankshaft. The drive is activated by a magnetic clutch. To regulate the boost pressure, a regulating flap is installed parallel to the compressor.
The twin supercharged TSI engine has a standard turbocharger. The charge air is cooled by an air-type intercooler.
Efficient operation of dual boost is ensured by the engine management system, which, in addition to the electronic unit, combines input sensors (intake manifold pressure, boost pressure, intake manifold pressure, control damper potentiometer) and actuators (magnetic clutch, control damper servomotor, boost pressure limiting valve, turbocharger recirculation valve).
Sensors monitor boost pressure at various locations in the system: after the mechanical supercharger, after the turbocharger, and after the intercooler. Each of the pressure sensors is combined with air temperature sensors.
Magnetic clutch turns on by signals from the engine control unit, at which voltage is applied to the magnetic coil. The magnetic field attracts the friction disc and closes it with the pulley. The mechanical compressor starts to rotate. The compressor works as long as the magnetic coil is energized.
Servo motor turns the control valve. When the damper is closed, all the intake air passes through the compressor. The boost pressure of a mechanical compressor is controlled by opening a damper. In this case, part of the compressed air is fed back into the compressor, and the boost pressure is reduced. When the compressor is not running, the damper is fully open.
boost pressure control valve is activated when the energy of the exhaust gases creates excess boost pressure. The valve provides a vacuum actuator, which in turn opens the bypass valve. Part of the exhaust gases goes past the turbine.
Turbocharger recirculation valve ensures the operation of the system at forced idle (with the throttle closed). It prevents overpressure from building up between the turbocharger and the closed throttle.
The principle of operation of the dual-supercharging TSI engine
Depending on the engine speed (load), the following modes of operation of the dual boost system are distinguished:
- naturally aspirated mode (up to 1000 rpm);
- operation of a mechanical supercharger (1000-2400 rpm);
- joint operation of the supercharger and turbocharger (2400-3500 rpm);
- turbocharger operation (over 3500 rpm).
At idle, the engine operates in naturally aspirated mode. The mechanical blower is off, the control damper is open. The energy of the exhaust gases is low, the turbocharger does not create boost pressure.
With an increase in the number of revolutions, the mechanical supercharger is switched on and the control damper is closed. Boost pressure is mainly created by a mechanical supercharger (0.17 MPa). The turbocharger provides a little extra air compression.
When the engine speed is in the range of 2400-3500 rpm, the boost pressure creates a turbocharger. The mechanical supercharger is connected when necessary, for example, during sharp acceleration (sudden opening of the throttle). The boost pressure can reach 0.25MPa.
Further operation of the system is carried out only due to the turbocharger. The mechanical blower is off. The control damper is open. To prevent detonation, the boost pressure drops slightly as the engine speed increases. At a speed of 5500 rpm, it is about 0.18 MPa.
Turbocharged TSI engine
In these engines, supercharging is carried out exclusively by a turbocharger. The design of the turbocharger ensures that the nominal torque is reached even at low engine speeds and maintained in a wide range (from 1500 to 4000 rpm). The outstanding characteristics of the turbocharger are obtained by minimizing the inertia of the rotating parts: the outer diameter of the turbine and compressor impeller is reduced.
The boost control in the system is traditionally carried out using a bypass valve. The valve may be pneumatically or electrically actuated. The pneumatic actuator is operated by a solenoid valve for boost pressure control. The electric drive is represented by an electric guiding device, consisting of an electric motor, a gear train, a lever mechanism and a position sensor of the device.
A turbocharged engine uses a liquid-based charge air cooling system, unlike a twin-charged engine. It has a circuit independent of the engine cooling system and forms a dual-circuit cooling system with it. The charge air cooling system includes: charge air cooler, pump, radiator and piping system. The charge air cooler is located in the intake manifold. The cooler consists of aluminum plates through which the pipes of the cooling system pass.
The charge air is cooled by a signal from the engine control unit to turn on the pump. The flow of heated air passes through the plates, gives them heat, and they, in turn, give it to the liquid. The coolant moves along the circuit with the help of a pump, cools in the radiator and then in a circle.
Every abbreviation in the automotive industry means something. So, the concepts of FSI and TFSI also matter. Only here is the difference between almost identical abbreviations. Let's analyze what is inherent in the names and what is the difference in them.
Characteristic
The FSI power unit is a German-made engine from the Volkswagen concern. This engine has gained popular popularity due to its high technical characteristics, as well as ease of construction, repair and maintenance.
The abbreviation FSI stands for Fuel Stratified Injection, which means layered fuel injection. Unlike the widely used TSI, the FSI is not turbocharged. Speaking in human terms, this is an ordinary naturally aspirated engine, which Skoda used quite often.
FSI engine
The abbreviation TFSI stands for Turbo Fuel Stratified Injection, which means turbocharged stratified fuel injection. Unlike the widespread FSI, the TFSI is turbocharged. Speaking in human terms, this is a conventional naturally aspirated engine with a turbine, which Audi used quite often on the A4, A6, Q5 models.
TFSi engine
Like FSI, TFSI has an increased environmental standard and economy. Due to the Fuel Stratified Injection system and thanks to the features of the intake manifold, fuel injection and “tamed” turbulence, the engine can run on both ultra-lean and homogeneous mixtures.
Pros and cons of using
The positive side of the Fuel Stratified Injection engine is the presence of dual-circuit fuel injection. From one circuit, fuel is supplied at low pressure, and from the second - at high pressure. Consider the principle of operation of each fuel supply circuit.
The low pressure circuit in the list of components has:
- fuel tank;
- gasoline pump;
- fuel filter;
- bypass valve;
- fuel pressure control;
The device of the high pressure circuit assumes the presence of:
- high pressure fuel pump;
- high pressure lines;
- distribution pipelines;
- high pressure sensor;
- safety valve;
- injection nozzles;
A distinctive feature is the presence of an absorber and a purge valve.
FSi engine Audi A8
Unlike conventional gasoline power units, where the fuel enters the intake manifold before entering the combustion chamber, on the FSI, the fuel enters directly into the cylinders. The nozzles themselves have 6 holes, which provides an improved injection system and increased efficiency.
Since air enters the cylinders separately, through the flap, an optimal air-fuel ratio is formed, which allows gasoline to burn evenly without subjecting the pistons to excessive wear.
Another positive quality of using such aspirated is fuel economy and a high environmental standard. The Fuel Stratified Injection system will allow the driver to save up to 2.5 liters of fuel per 100 kilometers.
Applicability table TFSi, FSi and TSi
But, where there are many positive aspects, there are also a significant number of disadvantages. The first disadvantage can be considered that the aspirated is very sensitive to the quality of the fuel. You can’t save on this engine, because on bad gasoline, it simply refuses to work normally and will malfunction.
Another big drawback can be considered the fact that in the cold, the power unit can simply not start. Considering common faults and FSI engines, cold start problems can occur in this range. The culprit is considered to be the same layered injection and the desire of engineers to reduce exhaust toxicity during warm-up.
Oil consumption is one of the disadvantages. According to most owners of this power unit, an increase in lubricant consumption is often noticeable. To prevent this from happening, it is recommended to comply with VW 504 00/507 00 tolerances. In other words, change engine oil 2 times a year - during the periods of transition to summer and winter operation.
Conclusion
The difference in names, or rather the presence of the letter "T", means that the engine is turbocharged. Otherwise, there is no difference. FSI and TFSI engines have a significant number of positive and negative sides.
As you can see, the use of aspirated is good in terms of economy and environmental friendliness. The motor is too sensitive to low temperatures and poor fuel. It was for the shortcomings that its use was discontinued and switched to the TSI and MPI systems.
Surely many paid attention to cars with the "mysterious" inscription TSI.
Moreover, this abbreviation is typical for cars not only of the Volkswagen brand, but also of other brands that are part of the VAG (Volkswagen Audi Group) - Audi, Skoda, Seat ...
What does this inscription mean for the driver of such a car?
From this article you will learn:
TSI decoding
The abbreviation TSI stands for Twincharger Stratified Injection, which means a twin-charged engine with stratified or direct injection.
TSI engine has a more complex design than a conventional one. Despite the relatively small and good power reserve, the TSI engine is more economical and reliable.
The main distinguishing feature of such an engine is the presence of a two-stage boost - the first "stage" is a supercharger with a mechanical drive, and the second "stage" is a turbocharger.
The mechanical compressor operates up to 2.4 thousand revolutions. The intake damper for airflow opens fully when the rotational speed exceeds 3.5 thousand revolutions per minute. It is then that a strong air flow enters the turbocharger and maximum torque is reached.
There are TSI engines in which a button is installed to select winter driving. This mode eliminates wheel slip due to softer operation of the motor.
What advantages does
The efficiency of the TSI engine, combined with its solid power, deserves special attention. The power unit always provides the car with good dynamics, thanks to two superchargers at once, because in a wide speed range you can achieve the maximum torque value.
The use of a combination of a mechanical compressor and a turbine allows you to maintain traction as much as possible over a long period of revolutions. In this case, the mechanical compressor works independently at low speeds, and when working together - at medium speeds.
The next no less important advantage is the low level of CO2 emissions. It should be mentioned that "TSI" was nominated as the best "green" engine of the year.
Among other numerous advantages of the "TSI" line, it is worth highlighting their sufficient reliability and relatively high resource.
What are the disadvantages
Like any thing, the TSI engine has some disadvantages. It should not be forgotten that most modern turbocharged VW engines are very demanding on the quality of fuel and oil. The TSI engine was no exception; for normal operation, it needs only high-quality fuel and.
In addition, the TSI engine requires the owner to strictly comply with the rules for operating turbo engines prescribed in the vehicle documentation.
In addition, a TSI engine can cause some discomfort in winter. The reason is that the TSI engine of the family has a low heat transfer and practically does not warm up when idling in the cold season. In general, the optimal temperature regime of this engine is achieved only while driving after a certain period of time.
But there is another side of the coin, already positive - such an engine is not prone to overheating even in extreme heat in a long traffic jam. However, this feature can cause discomfort during the operation of a car with a TSI engine for short distances: an unheated engine means an unheated interior, since the traditional “stove”, which uses engine antifreeze in its work, will be ineffective.
But VW engineers have foreseen all these nuances by creating a dual-circuit cooling system with two thermostats: one circuit cools the hotter cylinder head, the second - the rest of the powertrain block.
To increase the service life of the TSI engine, the turbine is cooled by its own system, which includes an electrically driven water pump, which continues to drive the coolant for another 15 minutes after the engine has stopped.
The use of direct injection in gasoline engines is the dominant technology in today's automotive industry. TSI is the abbreviation for Volkswagen's patented designation for turbocharged direct injection engines. Turbo Stratified Injection is used on most modern cars produced by the VAG-group (Audi, Skoda, Volkswagen and Seat). TSI technology is the next step in the development of FSI engines, which have direct injection, but are not equipped with a turbocharger.
Consider not only the principle of operation, but also a number of design flaws that are a serious headache for owners of TSI motors.
Advantages
TSI motors have a number of undeniable advantages:
- mixture formation. Focusing on the readings of the sensor equipment, the ECU can form 4 types of mixture (lean layered mixture with the addition of exhaust gases, a lean homogeneous mixture without the addition of exhaust gases, a homogeneous stoichiometric mixture with the addition of exhaust gases, a homogeneous stoichiometric mixture without the addition of exhaust gases). The choice will depend on the amount of air supplied, the degree of opening of the throttle valve, engine speed, engine temperature and other factors. This selective mixture formation allows you to get the most out of injected fuel;
- turbocharging, which allows you to increase the filling of the cylinders with fresh air. TSY motors can be equipped with a single-stage or combined air injection system. In the first case, the engine has a work which is known to many motorists. The combined system has not only a turbine, but also a mechanical supercharger of the Roots type. The principle of operation of such a system is of particular interest, therefore, we will consider it in more detail below.
- tuning potential. Most TSI engines lend themselves well to chip tuning. Owners who want to add a few dozen horses should think about the resource of the internal combustion engine and gearbox, which, if chipped incorrectly, can drop sharply.
The principle of operation of the injection system
The fuel supply system in the TSI engine is very similar to that used on. It consists of the following components:
The main feature of the direct injection system in the TSY engine is the control of the spray method and delivery time. This advantage is achieved by competent programming of the ECU. Otherwise, the power system, in fact, is no different from that used on engines from many other manufacturers.
Twin turbo system
In many ways, it was the combination of a turbine and a mechanical supercharger that allowed TSI engines to win more than one Engine of the Year title. Let's see how this solution is implemented.
The main principle of operation is the distribution of air flows. By changing the flow rate, as well as the amount of air supplied, it is possible to control the quality of mixture formation in the cylinders. Depending on the crankshaft speed and throttle position, the following turbocharging control algorithms can be distinguished:
Control
One of the main elements of this system is a damper that redistributes the air flow between the turbine and the supercharger. Adjustment is carried out by means of a servo drive. For example, at 1000-2400 rpm, air is supplied only through the supercharger, and after 3500 only to the turbocharger.
For competent control of this entire system, the ECU constantly polls a number of sensors:
- MAP sensor that measures the pressure in the intake tract. Air temperature is also measured;
- throttle position;
- pressure in the intake manifold and a sensor that measures air temperature;
- boost pressure, air temperature.
Of course, there are many subtleties, the explanation of which will require a serious deepening in theory.
Types of boost
The TSI engine can only have a turbine. The control is carried out using a bypass valve (electric or pneumatic). For example, with excess pressure in the exhaust manifold, the flow of exhaust gases will pass by the "hot" part of the turbine. The peculiarity of such a system is in the method of air cooling. A liquid-cooled intercooler is installed in front of the intake manifold. The air passes through the cells, inside which the coolant circulates. Cooling is activated by an ECU command that turns on the pump, thereby starting the coolant circulation in the air cooling circuit.
On a twin turbo car, the engine has an air-cooled intercooler.
Problems
Many owners are upset by the fact that their car has a TSI engine. Among the entire line of engines (1.2, 1.4, 1.8, 2.0, 3.0), some internal combustion engines can cause a lot of trouble to their owners. Among the main problems:
- zhor oil, which can begin after 10 thousand km .;
- chain stretching.
The problems of TSY motors are so significant that they require consideration in a separate article.
