Megane 175dci problem's

Hi guys/girls

I've got a 2008 megane 2.0l 175dci with a problem that none of my local garages can seem to fix,

Please help

The car starts and idols fine but when driving it there's no boost like the turbo isn't kicking in and won't rev past 3000rpm.
It's been remapped, dpf deleted and removed and egr set to 1% years ago,

No fault codes with clip and at the garages they have replaced the turbo converter (black and gray one by battery) checked the turbo, checked wastegate, and tried swapping the egr for another one but its just the same and ended up saying its the ecu

Took the car to my local auto electrician which said the ecu and turbo are fine and couldn't find anything wrong with the car,

Has anyone got any ideas?
Any help is very much appreciated

Thanks in advance
Brett