This is an interesting one. What exactly are the symptoms? Does it feel reasonably normal until hiway speed or is it dead across the entire band? Have you got an OBDll reader that provides the codes? Sounds to me like you have hit most of the problem areas, although the fuel pressure regulator can provide some of the problems you describe. I have never personally heard of an ECU failing, but it is possible. Can you borrow one from someone and just plug it in as a test, cause they are not cheap... IF it is the ECU, can you have it remapped anywhere around you?
Can you borrow a waste gate solenoid and try it out? if that has failed, it will give EXACTLY the symptoms you describe.
Finally, check (replace) the copper washers and seals on the injectors, they can also cause headaches.


By the way, my Td5 is purring like a kitten, gives me 31 mpg, and when I rev it there is no smoke - but it cost me some bucks to get it that way, mostly of the variety of what I am describing. I am very interested in this problem, and would love to know what it is.

 

There is no power when you pull away its as if you haven't pressed the accelerator. Its been on 3 computers and no one can work it out what it is.

 

Now I am starting to grasp straws, but there may be something - your throttle is not directly connected, there is a 'throttle position sensor' or something like that. Is yours working properly? It is tough to figure out without codes, though....

 

The TPS did not come up on the fault codes but it is one of the next things we are going to check. First I am going to talk to a couple of ECU repair company's. I'm just waiting for 9 0 clock to ring them.
Thanks for your help I will keep you posted
Bob

 

And please don't underestimate the importance of the stupid little copper washers and seals on the injectors. I did. Cost me about a grand replacing other stuff that probably was fine.

 

Been told don't clean the ends of injectors That might be the problem. Will know when have another set fitted.

 

Lesson learnt don,t clean electronic injectors. Fitted a SH set which I was told are only 12 months old. Did not know she had so much power absolutely flies.

 

Many TD5's suffer loss of power also from clogged EGR's or MAP sensors. I don't have the problem as I removed the EGR some time back. It really depends on your emissions gurus when they do the checks and testing for an MOT or whatever you have where you are.