Check the in-line filter situated between the tank and the pump. Look below the L/H doors, mounted on the inner side of the chassis. Sometimes stealers ignore replacing this filter. To have a quick look at the turbo, try removing air inlet pipe and look as best you can if the turbo has obvious blade damage and try wiggling the impeller. Mine has 83K on the clock but has just the slightest movement (play).
My trokkie, called Hoss, has been visiting the stealers regularly lately, to the extent it's on first names basis with the back room guys.
Steed 2.8 D/C 4x4 Dastek Chip, Gabrial Safari's front, Monroe Gas rears. Torsion bars adjusted.