Mike, have you heard of Revive?
Marketed by SP diagnostics, I have used it several times now with very good results.
It is also available through Andrew Page or Camberley Auto Factors.

http://members.boardhost.com/ukautotalk5/msg/1323444689.html

>>The vehicle has only done 48000 miles and not driven hard knowing the owner<<

Most probable cause of semi siezed vanes & control ring.

Cheers, Tony.