Hi , I'm having problems with my 2010 2.0 cdti insignia 

I've got an overboost problem . While on tickover I get a thump noise from the wastgate solenoid followed by the service vehicle soon message . I have changed the solenoid/ wastegate actuator/ map sensor cleaned the maf sensor and the egr valve and also changed the intercooler pipe . While driving if I get the message it drops to low power not limp mode ? I also have no engine management light .

Many thanks 

Dave

I would run a scan on the system and see what codes appear.

Sounds like the pressure is building up in the turbo but also could be variable vanes gummed up and may benefit from running some turbo cleaner through it