Problems with Steering wheel 02 reg 607

[m561srs]

I just got 02 plate 607 2.2 HDI Diesel, which had done 97,000. I have a big problem with steering wheel that drive me crazy.

It does not work fine as it should be. really tight.
it is not tight through it turning whole time.
let say 360 degree turning.
first 20 degree is fine, then next 20 degree is tight, then become fine again, then tighter again, and so on.

can anybody tell me what wrong with it. if so which part should be change

[Scotcruz]

sounds like your steering pump is gone.. have you checked the fluid in it? can you notice any fluid leaked near the pump or the drive belt ?