Focus MK2 tdci issues

[customnpaint]

Hi I have got issues with my 2010 ford focus MK2 2.0tdci when I attempt to start for the first time it start ups bet then slowly cuts out but then when start it for the second time it idles and runs fine sometimes when driving it loses boost so then when you turn it off and start is back up it's fine again

Got fault codes
1.P0234-A1 Turbocharger/Supercharger Overboost
Condition

2.P2263-E1 Turbocharger/Supercharger Boost System
Performance

Person I bought the car off said they changed the wastegate don't know if that is true or not they said it it was the boost control solenoid so I changed that but still the same I have also changed the map sensor and also cleaned the egr system and throttle body yesterday

Does anyone know what this could be



Also what is this part in the picture looks similar to the boat control solenoid

Thanks