Rasping-like sound when accelerating, power-loss, car is juddering when accelerating
 

Hello all,

(Sorry for not introducing myself more formerly)
1.) I know nothing - to very little about cars in general and how they work.
2.) This car was fully-serviced approximately 3 months back
3.) The car was bought second-hand in winter of 2015
4.) When I first bought this car, there existed a Turbo-related problem that was never repaired or addressed by me. Basically, above 3,500 Revs the engine would go into 'LIMP' mode.
I have enjoyed over 20,000 miles of driving across Europe with this Turbo-problem. I just ensured that when changing gear I did so when driving under 3,500 Revs

I have a 2004 X-type 2.0D 4-door saloon - Sovereign spec.
Symptoms:
1.) Recently, the engine is making a horrible 'rasping-like' sound when I accelerate.
2.) Also, when I accelerate the car judders forward.
3.) there seems to be a 'loss' of power somewhere as I do not get the 'turbo-kick' that I am used to when I accelerate.
4.) alot of black-smoke billows out from the exhaust

What I have done (so far):
1.) Today, I poured into the fuel-tank:- Injector-cleaner fluid & turbo-cleaner fluid
2.) topped-up the fuel-tank with diesel fuel
3.) I left the car in Neutral then Revved the engine to about 4,000 Revs. When I do this I do not hear that worrying 'rasping-like' sound

Any advice on what the problem is or might be.
Mechanically, I am a real simpleton - so I would appreciate any and all 'non-techie' help from you.

First of all driving a car for 2 years that goes into "limp mode" is sorry to say just plain idiotic. Then wonder why there are problems. Really?

Try looking under search function for "Mr. Muscle" fix. Worth a shot for giggles.