I have a 97 Explorer Limited 4WD 4.0 SOHC. My power steering went out a few months ago. After talking with friends and mechanics, I decided to replace both the pump and the rack. After installing both and getting everything back together (I even remembered to pull the power steering pressure valve out of the old rack and put it into the new rack), I filled up the reservoir and started it up. I continued to fill the reservoir while bleeding the system by moving the steering wheel from side to side. The pump was noisy at first but it quieted down after about 15 minutes. The reservoir is now at the max mark and the fluid is no longer foamy looking; it is clear and calm.
Here's the problem: In park at idle, it acts as though there is no power steering, the steering wheel is very difficult to turn. If i step on the gas to bring up the RPMs, the wheel turns fine. This is true while driving too, no matter what speed, if the engine is running slowly (~800 RPM) the wheel won't turn, but if I step on the gas it turns fine. Only a few hundred RPMs makes a difference, it will turn fine at about 1100RPM.
What is the problem here? Do I need to give the pump more time to break in?
Thanks for the help, Dave