Turbocharger – function, defects and repair

If you are thinking about buying a new or recently used car these days busy, you will hardly be able to do without a turbocharged engine. Torque and power can be massively increased here, although the mechanics remain the same. We explain here how this is possible.

Anyone who owns a combustion engine and would like to increase its performance has certainly dealt with the exhaust gas turbocharger at some point. This is all about a system where exhaust gases from the engine drive a turbine, with the rotation of the compressor wheels delivering more fresh air to the engine. At that time this was still a breakthrough of the new development, but today the turbocharger is mostly a standard feature on diesel and petrol engines. It is also known here that the use of a turbocharger means that a smaller engine with less power can be fitted, which means it consumes less fuel but can still deliver high performance.

Disadvantages of these systems, however, are expensive repairs and damage to the engine that is not easy to repair. While everyone still knows that displacement is the be-all and end-all, nowadays displacement can be replaced without sacrificing performance. Because: as soon as less cubic capacity and therefore fewer cylinders are fitted to a vehicle, there is also less friction and thus lower fuel consumption. This means that even a 1.6 liter petrol engine with 4 cylinders can produce up to 270 hp. Decades ago, up to eight cylinders had to be installed for such a performance.

What is the function of a turbocharger?

Experts also call the turbocharger exhaust gas turbocharger, because they know exactly how it actually works: it uses the energy of the exhaust gases to charge the engine with fresh air, which is why these systems are also called the “charged engine”. In general, a turbocharger is constructed as follows: there are two turbines, the compressor wheel and the turbine wheel. Particularly powerful turbo engines usually also have an intercooler, which ensures that part of the heat produced when the air is compressed is dissipated.

The charge-pressure regulation – Avoiding overload

In order to prevent the boost pressure of the turbocharger from reaching a level that can become critical, the pressure must be regulated. Otherwise, it will overload the turbocharger. Other engine components can also be affected. This regulation is usually controlled via a valve, whereby when it opens, the exhaust gases are guided past the turbine wheel, so that the boost pressure is reduced here.

How do I optimally care for the turbocharger?

Adequate lubrication is an absolute must here. Once the engine has started, it takes about 30 seconds for the oil to spread evenly, so it is important to avoid high revs during this time. However, if you have demanded high performance from your vehicle after driving, you should also wait around 30 seconds before you switch off the engine. Let it run at low speed for a while first. Good lubrication is always guaranteed when the engine is still running. Also, make sure you only use oils that are recommended by the manufacturer. You shouldn't dare to experiment here. Also, avoid mixing different oils. Stick to one type.

Defects of a turbocharger

The turbocharger is usually damaged when the oil supply is not guaranteed, because the connecting parts between the turbine wheel and the compressor wheel should be supplied with oil throughout, if this is not the case, the shaft can be damaged and even in one crack ends. A deficient supply of oil can occur if there are foreign particles, bad oil or fuel in the oil. In addition, you should absolutely avoid switching off a turbocharger when it is still hot, because under high loads the exhaust side can heat up to 1000 degrees Celsius here.

But foreign bodies that get into the intake tract often end up in defects. Since the speed of rotation is so high here, even small particles can quickly cause damage. Other signs of turbocharger damage include turbocharger whistling and blue smoke, as well as increased fuel consumption, black smoke, loss of actual power, excessive boost pressure and strange noises. However, the solenoid valve, as well as the membrane or the hose system, which is located between the components, can also have a defect or a leak.

Repair of the turbocharger

There are a variety of signs of turbocharger defects: increasing oil consumption, heavy smoke, whistling noises or the like – if you notice these signs in your vehicle, you should not hesitate and go straight to a workshop to get advice from experts. There can be so many causes of defects here that you cannot identify and assess without the necessary specialist knowledge. If you wait too long before visiting a workshop and the turbocharger is completely defective, the defective parts can also quickly damage the rest of the engine. In addition, if a lot of oil is lost, the catalytic converter can be damaged, which in turn can be very expensive. Depending on the complexity of the repair work, you can expect costs of between a few hundred euros and several thousand euros. Don't let it get that far and act immediately!

The conclusion and a tip from CarTipsandmore: The turbocharger has become indispensable in the automotive industry today. It provides an increase in performance that could otherwise not be achieved with smaller engines. But repairs can be expensive here. Therefore, take good care of your turbocharger by ensuring that the components are adequately lubricated. As soon as signs of defects appear – be it a whistling of the turbocharger, as well as bluish smoke, as well as increased fuel consumption, black smoke, as well as a loss of the actual power, an excessive boost pressure, as well as strange noises – then you should not hesitate and visit a workshop immediately. Repairs to the turbocharger are a job for professionals and should never be carried out by laymen. So fully rely on the knowledge of professionals here and avoid DIY repairs.