Hi All.
Thought I would share the culmination of Many Many months of frustration (and muchos ££££££'s)
Had recurring and developing warnings for turbo not reaching correct position as this got worse it then gave me (as well as the car) LIMP MODE !!! .... A K A Restricted performance. lots of investigation later including Beadles of Southend (waste of time ) and also changing air/vac valves, intercooler tests/ pipe leaks _ etc etc ... i stumbled upon reference to variable vane turbo cleaning (Forte cleaner) decided to try this at max strength, 1/2 tank diesel and two bottles added. Guess what .. It blew up my small turbo and proved which unit was giving all the problems. renewed small turbo. raced around like an idiot for a week or so - no warnings / limp mode or anything else .... then suddenly limp mode !!! Well (me thought ) I know its not the small turbo so perhaps the large turbo which is the original unit is also dirty ?? so two bottles Forte, 1/2 tank diesel (Esso synergy) cross my legs/fingers/eyes and off we go - two further limp modes, prompted by 'lively' driving then suddenly no further issues or alarms even when driving like I stole it. So my findings for what they are worth is the turbos really suffer from carbon build up and as soon as you get a related warning stick in a bottle (or two) of Forte and see what happens. Prior to all this my DPF was working overtime (now know why with faulty turbo and suspect sensor) and eventually blocked, Had it cleaned at ace turbo. %20Contact@AceTurbo.co.uk who made it an easy job arranging pick up and return.
So now = Happy Bunny with my (wolf in sheep's clothing) old mans car, back up to 'Lively' performance

Ps. Tried changing the 2004/5 S Type etc etc below, but couldn't ???