Bongo Fury

From what you said, it runs fine with filter removed and lid attached. Have you checked the inlet pipe for any obstruction?

I think you will find that without the filter element fitted, the lid doesn't actually seal so any obstuction in the inlet pipe won't show in the symptoms.

OK. Think I need to start this again. Don't get to run the bongo that often so still trying to get used to the way it runs.

The problem is still there even with the filter and lid removed.
Not sure what happened the first time, must have had a bit more of a run up when I tryed it.

Have checked all the hoses and there all OK.
All filters are new.
Banjo filter is spotless
Broken Non return valve has been fixed

I'm not getting any boost from the turbo until 3200rpm, so when I get to a hill I have to floor it so it kicks down a couple of gears to get the revs up. The boost kicks in, bongo changes up a couple of gears, lose all power and slows down, so i have to floor it again to get to revs up and so on until I reach the top of hill.
Happens on the smallest of inclines.

That does not sound normal - take it back.

Definitely go back to the dealer - as I understand it, dealers are responsible for problems that are there when vehicle is sold. They may not have been aware of the problem, so let them know and give them a chance to rectify it.