When you say "mechanically everything is fine" what all did they test? Did they hook up a pressure gauge into the lines and verify the pump is putting out 10-11MPa's ? That will verify the pump is good. There is also another test that you turn a torque spanner (installed in steering wheel) each side until the pressure in the lines is 1.2 MPa. The spanner should indicate its only 2.5-3.5 Nm to turn it, otherwise your steering gear is shot (or in the process of going...) .

You should be able to call the shop and verify these tests were done to clear your steering gear and your pump. I'm wondering if perhaps your pump is having issues keeping the pressure up while you use it.. I don't think you want to hear this, but the dealer shouldn't charge more than an hour and a half to do this.



I'm hoping someone can confirm or correct me, but I don't think the speed-sensitive steering didn't come around until '04. Therefore I'm not entirely sure what electronics could be causing intermittency..