Initially the issue was that my steering wheel would occasionally 'lock up' - become really stiff in certain situations.

Basically I have had the power-steering pump and a steering tie rod replaced under warranty and now the steering effort is really high. Especially at parking speeds. My power-steering box was also replaced, but the new one was malfunctioning (supposedly a bad soleniod), so they put my old one back on.

Steering seems to function fine otherwise; no more 'lock ups'.

Do you guys have any idea what it can be/how to regain that perfect steering effort E38 has?

Thanks!