Volkswagen concern cars are quite common in Russia. One of the features of these cars is turbocharged engines. And if earlier the turbine could be found only on diesel engines, then VAG uses it everywhere on gasoline engines.
The purpose of modernization is to maximize the technical characteristics of the unit while maintaining its working volume. Since fuel efficiency is important today, the volume of the combustion chamber cannot be infinitely increased. Therefore, car makers go to different tricks. A striking example of such work is the TSI engine. What is it and what are the features of this power plant? Consider in our article today.
Characteristic
The TSI engine is a gasoline power unit that is used on Volkswagen, Skoda and Audi cars. A characteristic difference of the TSI engine is the presence of a double turbocharger and a direct fuel injection system (not to be confused with the Common Rail). Having developed a special design, German engineers achieved high fuel efficiency of the unit with good technical characteristics.
The first TSI sample appeared in 2000. This abbreviation literally translates as "double boost layered injection."
Aggregate line
It is quite extensive, and motors with the same displacement can produce different powers. A striking example is the 1.4-liter TSI engine. 122 horsepower is far from a threshold threshold. The concern also produces 1.4 TSI engines for 140 and 170 horsepower. How is this possible? It's simple: the differences are in boost technology:
- when using a single turbocharger, the engine power of TSI 1.4 varies from 122 to 140 horsepower;
- using two turbines, the power increases to 150-170 forces. This changes the software of the electronic engine control unit.
And all this on a motor with a displacement of 1.4 liters! But this is not the only motor in the line. There are different variations of TSI engines:
- 1.0 TSI. This is the youngest motor. It is equipped with a single turbine and develops a capacity of 115 horsepower. The TSI liter engine has just three cylinders.
- 1.4. We have already talked about these motors above. In the lineup there are five engine variations with power from 122 to 170 horsepower. All cylinders are arranged in one row.
- 1.8. Such motors have three modifications. The power of this power plant can be from 152 to 180 horsepower.
- 2.0. These units develop power from 170 to 220 forces. The engine block is in-line, four-cylinder (as in the previous two units).
- 3.0 This is the flagship motor used on the Volkswagen Tuareg. This is a V-type six-cylinder engine. Depending on the degree of boost, its power can be from ZZZ to 379 horsepower.
As you can see, the range of powertrains is quite extensive.
Device
It is worth noting that the TSI engines are substantially redesigned. So, an aluminum cylinder block, a modified intake and exhaust system, as well as an upgraded fuel injection system are installed here. However, first things first.
Superchargers
The turbine is the main element due to which such high technical characteristics are achieved. Superchargers on TSI motors are located on different sides of the unit. The mechanism is powered by exhaust energy. The latter drive the impeller, which through special drives pumps air into the intake manifold. Note that conventional turbocharged engines have a lot of disadvantages. In particular, this is the effect of a turboyama - the loss of engine torque at its certain revolutions. TSI motors are free from this drawback due to several superchargers. One works at low speeds, and the second connects at high speeds. Thus, maximum torque is realized in a rather wide range.
How does boost work?
Depending on the number of revolutions of the crankshaft, the following modes of operation of this system exist:
- Naturally aspirated. In this case, the turbine is not involved in the work. Engine speed does not exceed one thousand per minute. The throttle control flap is closed.
- The operation of a mechanical supercharger. This mechanism is activated when the speed is from one to two and a half thousand per minute. A mechanical supercharger helps provide good torque when starting the car from a standstill.
- Joint operation of the turbine and supercharger. This occurs at speeds from two and a half to three and a half thousand.
- Turbocharger operation. The supercharger is no longer included in the operation. Supercharging is provided only by the impeller of the turbine in a speed mode of three and a half thousand and higher.
With increasing speed, air pressure also increases. So, in the second mode, this parameter is about 0.17 MPa. In the third, the boost pressure reaches 0.26 MPa. At high speeds, the pressure level decreases slightly. This is done in order to prevent the effect of detonation (spontaneous ignition of a gasoline mixture, which is accompanied by a characteristic blow on the piston bottom). When the turbocharger is operating, the pressure level is 0.18 MPa. But this is enough to provide high torque and power when driving at speed.
Cooling system
Since the engine is in constant load mode, it needs high-quality cooling.
So, the system has nozzles that pass through the intercooler. Thanks to this, cold air enters the cylinders. This provides a more complete combustion of the mixture and contributes to the growth of engine dynamics.
Injection system
The TSI engine has an upgraded injection system. It refers to the immediate type. So, the fuel enters the chamber immediately, bypassing the classic fuel rail. According to reviews, the work of direct injection is felt at a set speed. The car is literally undermining from the bottom. But the use of such an injection system is not only aimed at increasing efficiency and engine power, it helps to reduce engine fuel consumption.
Cylinder block
The TSI engine features a lightweight engine block made of aluminum. The use of such an alloy significantly reduced the mass of the motor. On average, such a unit weighs 14 kg less than cast iron. Other camshafts hidden behind a plastic cover are also used in the design. Thus, high operational performance of this engine is achieved.
Problems
What are the TSI engines problems? One of the common diseases of these power plants is increased oil consumption. Moreover, maslozhor is not uncommon even on new engines. What do 1.4 TSI engine reviews say? These units consume up to 500 grams of oil per 1000 kilometers. This is quite a lot. Owners often have to control the level with a probe. If you miss the point, you can catch oil starvation, which is fraught with a decrease in the resource of the TSI engine, namely its piston group. Can this problem be solved? Unfortunately, this is an "incurable disease" of all TSI engines, so the owner only needs to regularly monitor the dipstick and carry a bottle of oil with it to top up.
Another problem that put an end to the reliability of the 1.4 TSI engine is the failure of the turbine. It is often “thrown” with oil, and by 80 thousand bearings play appears. The turbine is not able to pump air at the right pressure, which worsens the flow dynamics and changes the behavior of the car. The cost of repairing a supercharger is about 60 thousand rubles, and there are several such turbines in the engine.
The next pitfall that casts doubt on the reliability of TSI engines is the gas distribution mechanism. They work from a chain that is often stretched. The reason for this was excessively high loads. In recent years, the German manufacturer began to install a belt drive. According to the manufacturer, its strength has doubled. This somewhat improved the situation, however, there were still a lot of cars with an old timing chain on the market.
How much does the TSI engine serve? According to the manufacturer, its resource is about three hundred thousand kilometers. However, in practice, these motors run 150-200 kilometers. What significantly aggravates the situation is the aluminum block. It is practically unrepairable. There are no familiar wet sleeves that could be replaced, so in case of failure, the TSI motor is easier to replace with a new one, which, incidentally, is quite expensive.
Conclusion
So, we found out what the TSI engine is. The idea of creating this motor is not bad. The Germans sought to make a powerful and productive engine, to get maximum efficiency from it. However, in pursuit of ideal characteristics, the engineers did not take into account the mass of nuances that were already corrected in the process of mass production of engines. Should I buy a car with such an engine? Experts give a negative answer, since the resource of these engines is really small. Chain drive problems are also common. Despite the high performance and low fuel consumption from buying such a car is worth refraining. The owner may face unforeseen repairs and quite a serious investment.