Power issues,

Got a disco 300tdi and as of late I've noticed it's started lacking power esp, uphill. It starts and runs as sweet as can be, just when gets to between 2-2500rpm, the boost dies off completely up till then it's fine. So far I've changed the lift pump, filter, the copper washers and bleed the system as read up could be a fuelling problem but no luck as of yet. Was wondering if anyone else has heard or had this problem as starting to drive me a bit mad.
Thanks in advance

Try here, blokes got same problem.

http://www.landyzone.co.uk/lz/f8/power-issues-191959.html

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