A turbocharger is used to boost the engine's power. By increasing air pressure in the intake manifold, the air-fuel mixture that enters the combustion chamber increases boosting power. An engine that is equipped with a turbocharger requires a lower compression ratio and heat resistant valves. Also a specially designed crankshaft, pistons, rods, and other modifications are needed in order to the withstand the system's increased output of power.
The most common problems that arise with a turbocharger are blue exhaust smoke, excessive noise, and lost of power. When any problem arises, it would be best to take it to a professional mechanic to prevent any further damage to the turbocharger.
Turbochargers are usually covered under the powertrain warranty portion of the manufacturer's factory warranty. For extended coverage of the turbocharger, extended car warrantys are available that will cover the turbocharger after the factory warranty has expired.