Troubleshooting turbocharger as described below.

Turbochargers channel fouling. Within the compressor or turbine gas air passage channel serious fouling, so that the channel resistance increases, it will cause compressor surge, should be regularly washable supercharger.
(2) booster pressure drop. When the boost pressure reduction, to reduce the inflatable volume of the diesel engine, power down, increase fuel consumption, exhaust temperature. Therefore, the pressure is reduced by 10% when found, should stop to check.
Muddy dust and air filter blocked the intake resistance increases, compressor suction loss increases, resulting in a pressure drop, and you should clean or replace the air filter.
Compressor channel dirty. Effects due to poor air filter dust, dirt and oil, etc. adhere to the impeller and diffuser passages of the turbocharger, the airflow resistance increases, supercharging compressor efficiency and pressure drop. To prevent this phenomenon, in addition to maintaining or improving the air cleaner filter effect, but also regular washable compressor.
Turbines coke. Due to poor combustion and diesel engine turbocharger seal failure and leakage in the turbine blades, the formation of coke ring seal between the shaft and the rotor rotation increases resistance, speed down, engine parts uk so that the diesel engine starting difficulties and poor acceleration. Remedy is to prevent burning oil, regular washable turbocharger.
Gas sealing performance of the seal is damaged or diesel engine turbocharger compressor cylinder is decreased, the result is that, while the turbine speed down the gas leakage, so that air leakage of the other compressor inlet flow rate decreases, both of which can lead to the supercharging pressure reduced. Remedy yes, replace the compressor gas seal and three diesel engine maintenance, recovery cylinder sealing performance.
Boost pressure regulating valve regulating spring failure due to high temperature, discharge valve closed due to lax coke and other reasons the regulator valve failure, at a lower boost pressure value is to let go of more gas ,peugeot 307 turbo resulting in lower boost pressure, this time to deal with the boost pressure control valve for maintenance.
Poor exhaust turbine exhaust resistance increases, the gas expands in the turbine subject to certain inhibition, resulting in reduced power turbine, turbocharger speed down, the pressure is reduced, the reason is the exhaust pipe exhaust muffler deformation or obstruction and so on.
The nozzle ring for a long period under high temperature, deformation of the blade, so that the cross-sectional area of the nozzle ring increases, the rotor speed and the boost pressure is lowered.
A turbocharger connected to the intake pipe of the diesel engine cylinder head or the inlet leak.
Because of the turbocharger bearing wear, rotor impeller housing grazing, or debris blocking, so the boost pressure with decreasing rotor speed decreases.
        Diesel turbocharger is a high-temperature environment super-high-speed rotating machinery, its working speed of up 80000-120000r / min, up 200000r / min. Such a high-speed rotating machinery often due to improper installation, use and cause damage. Turbocharger life are lower than expected useful life of more than 90% is the main reason due to installation or improper use of the vehicle seriously overloaded or user-induced changes in oil characteristics.