Ruairi2021

Hi Guys! I have 2012 octavia 1.6 tdi and im going through a nightmare. When i go hard on the accelarator on a hill the car goes into limp mode and coil light shows up. everytime ive plugged it in it comes up as underboost... Have replaced 2 actuators that it says is the fault and also 2 map sensors aswell as cleaned out the turbo vains! 2 mechanics have said they have no clue what to do further. The car is fine driving around town its just when i come to a hill and i push on the accelarator its goes into limp mode.... when i turn engine on and off its fine again. would anyone have any solutions before i go crazy? lol