Boost pressure control swing valve/poppet valve does not close
Dirty air filter system
Dirty compressor or charge air cooler
Engine air collector cracked/missing or loose gaskets
Excessive flow resistance in exhaust system/ leakage upstream of turbine
Foreign body damage on compressor or turbine
Fuel system/injection feed system defective or incorrectly adjusted
Insufficient oil supply of turbocharger
Suction and pressure line distorted or leaking
Turbine housing/flap damaged
Turbocharger bearing damage
Valve guide, piston rings, engine or cylinder liners worn/increased blow by

Coke and sludge in turbocharger center housing
Crankcase ventilation clogged and distorted
Dirty air filter system
Dirty compressor or charge air cooler
Excessive flow resistance in exhaust system/ leakage upstream of turbine
Oil feed and drain lines clogged, leaking or distorted
Piston ring sealing defective
Turbocharger bearing damage
Valve guide, piston rings, engine or cylinder liners worn/increased blow by

Dirty compressor or charge air cooler
Engine air collector cracked/missing or loose gaskets
Excessive flow resistance in exhaust system/ leakage upstream of turbine
Exhaust gas leakage between turbine outlet and exhaust pipe
Foreign body damage on compressor or turbine
Insufficient oil supply of turbocharger
Suction and pressure line distorted or leaking
Turbine housing/flap damaged
Turbocharger bearing damage

Boost pressure control swing valve/poppet valve does not open
Fuel system/injection feed system defective or incorrectly adjusted
Pipe assy. to swing valve/poppet valve defective

Foreign body damage on compressor or turbine
Insufficient oil supply of turbocharger
Turbine housing/flap damaged
Turbocharger bearing damage

Coke and sludge in turbocharger center housing
Crankcase ventilation clogged and distorted
Oil feed and drain lines clogged, leaking or distorted
Piston ring sealing defective
Turbocharger bearing damage
Valve guide, piston rings, engine or cylinder liners worn/increased blow by

Coke and sludge in turbocharger center housing
Crankcase ventilation clogged and distorted
Dirty air filter system
Dirty compressor or charge air cooler
Excessive flow resistance in exhaust system/ leakage upstream of turbine
Oil feed and drain lines clogged, leaking or distorted
Piston ring sealing defective
Turbocharger bearing damage
Valve guide, piston rings, engine or cylinder liners worn/increased blow by

Boost pressure control swing valve/poppet valve does not close
Dirty air filter system
Dirty compressor or charge air cooler
Engine air collector cracked/missing or loose gaskets
Excessive flow resistance in exhaust system/ leakage upstream of turbine
Foreign body damage on compressor or turbine
Fuel system/injection feed system defective or incorrectly adjusted
Insufficient oil supply of turbocharger
Pipe assy. to swing valve/poppet valve defective
Suction and pressure line distorted or leaking
Turbine housing/flap damaged
Turbocharger bearing damage
Valve guide, piston rings, engine or cylinder liners worn/increased blow by

Coke and sludge in turbocharger center housing
Crankcase ventilation clogged and distorted
Dirty air filter system
Dirty compressor or charge air cooler
Excessive flow resistance in exhaust system/ leakage upstream of turbine
Oil feed and drain lines clogged, leaking or distorted
Piston ring sealing defective
Turbocharger bearing damage
Valve guide, piston rings, engine or cylinder liners worn/increased blow by

The turbocharger is designed such that it will usually last as long as the engine. It does not require any special maintenance; and inspection is limited to a few periodic checks.
To ensure that the turbocharger's lifetime corresponds to that of the engine, the following engine manufacturer's service instructions must be strictly observed:
Oil change intervals
Oil filter system maintenance
Oil pressure control
Air filter system maintenance

90 % of all turbocharger failures are due to the following causes:
Penetration of foreign bodies into the turbine or the compressor
Dirt in the oil
Inadequate oil supply (oil pressure/filter system)
High exhaust gas temperatures (ignition system/injection system)
These failures can be avoided by regular maintenance. When maintaining the air filter system, for example, care should be taken that no tramp material gets into the turbocharger.