Fault codes P1236 & P1044 help

[accordian]

The car is 2005 ctdi tourer, and it has gone into limp mode and managment light on dash plugged my obd reader and have 3 faults p1236, P1044, and the other just comes up N/A

Help help or advice much appreciated

 

[F6HAD]

Over boost and possibly injector 4 error. Clear them off and see which ones return

Check to ensure the electrical connector is firmly Connected to each injector

You may have a boost leak, sticking turbo actuator or turbo vanes and also possibly a faulty EGR valve