General 2005 scudo help

[hwads]

Hi
I have a 54 plate 2.0 jtd scudo (2005)
about a month ago I set off to work and after about half a mile the van lost power while i was turning at a junction it coughed and spluttered then all was fine (engine cold) then same again 2 or 3 times (engine warm).
now when starting from cold it starts fine but runs lumpy and when you press the gas peddle it gradually builds up revs where i need 3/4000 rpm to set off,
once over a certain rpm it runs ok. Once warm it runs ...ok but like a normal diesel (no turbo) until the turbo comes in, it used to be smooth constant power.

Help please

 

[r masters]

try unplugging air mass flow and see if it runs any better