The power steering on my 93 spec WRX has gone wrong, its really heavy. Tried flushing the system to no avail and the rack and pump look fine. Have been told its probably the seals inside one of the two that have gone, but dont know which. Is there a test or is it a case of buy one and swear my tits off when its the wrong one.... lol

Any idea on which one its more likely to be