Impreza Power steering

[BIG DUNC]

Car is '98 Impreza turbo 2000, with about 100k on the clock.
Recently the power steering has got very noisey at low ( parking ) speeds. There is no noticable difference to the feel of the steering or the way the car drives, its just noisy when you park.
The fluid level is OK, and there is nothing visably wrong.
Is this likely to be the rack or the pump on the way out?
Also, how quickly will it get worse? Will it remain "just" noisy for ages, or will it quickly develope into a more series problem?

[AndyB_WRX]

The power steering reservoirs have a habit of lying, try topping it up and see if it doesn't disappear

[PGM]

Had the same on mine at that mileage. THe fluid tends to get hot and not work as well over a period of time.

Replaced the power steering fluid and no further problems.

I basically siphoned the reservoir out, replaced with clean fluid and turned the steering from lock to lock 4 times. Repeat this process until you've used up nearly all the new fluid (normally a 1l bottle), leaving some for topping up. The new fluid is red, the old will be brown, you will see when the siphoned material is red that you have got all the old fluid out.

Check all is OK driving and check whether it needs topping up after a couple of days.

Cheers
Paul

[BIG DUNC]

Thanks for that.
I will refresh the fluid this weekend and see what happens.