I recently purchased a 95 maxima gxe 79K miles. Power steering is perfectly
fine while driving in high speed.

While stopping and going slowly (less than 5 mph), the power steering creates a
loud buzzing noise. An other weird noise comes when I steer fully to left or right.
The noise is as if a spring is realesed every half way of the steering cycle. The
spring-like noise gets worse is the steering cycle is close to complete.

1. Is this problem serious? Can I live with it?
2. A friend of mine claims that it is about the pump or the seal. Does it make
sense?
3. How much would it cost to fix the problem?

Thanks for all the help.