Hi.if your happy that the turbo shaft,com wheel and centre housing are free from damage then i would first look at the waste gate actuator.to test this you will need a pressure pump with gauge, pump up to aprox 15 psi and check this dose not fall away. disconect actuator from waste gate lever and check this moves free in both directions if this is not the case the this is poss the fault,The std max boost pressure for the 200tdi is 13psi. If can be any more help just shout. regards turbo tomo.
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