Td4 loss of power/smoke

if you havent sorted it , maybe try cleaning the MAP sensor this is located in the airbox, looking at the engine its tucked away at the left hand side, remove and clean with solvent cleaner ,, the amount of crud that can accumalate in the airbox is quite unreal, if the sensor becomes blocked, (its only a tiny hole), it wont control the turbo vanes correctly
hope this helps

another thought , make sure the small vacuum hoses are intact, they can rub and cause a hole to apear,

i did have a split vacuum hose and i am sure that it was causing me issues, thanks for the heads up on the MAP.

the landy has been sat on the drive while i wait for the time to get busy again (and the weather!) but fuel filter and MAP are two good places to get going on.

I will post results and photos if i can work out hoe to do it from my iphone!

thanks again for all advice!