You’re probably pulling air into your power steering system
I have a 1992 Ford Taurus that has been in my family since 1995. A number of years ago the car developed a problem in the power steering system. It began as a “floating then slight grab” as it was being driven around a long slight curve to the left or right.
In an effort to remedy the problem I changed the power steering pump with a “lifetime warranted” pump. The problem continued. Thinking the rebuild was at fault, I replaced it with another pump. There was still no solution. The next move was to replace the rack-and-pinion, which I did, but the problem was still present. The next things I replaced were the outer tie rod ends. The inner tie rods were included with the rebuilt rack-and-pinion. There was still no solution to the problem. I changed the power steering pump a couple more times without success. I then decided to live with the problem.
After selling the car to my granddaughter, I tried again by changing the power steering pump along with the low and high-pressure lines. The problem persists. Do you have any other suggestions?
I think we can safely say that the problem is not with the power steering pump per se. A common issue with Taurus power steering is air in the system. It can be difficult to totally purge all of the air out and the presence of air bubbles can cause erratic power assist.
To purge the air out, raise and support the front of the car so the wheels are off the ground. Turn the steering wheel from one extreme to the other to work air bubbles toward the high point in the system, which is the power steering fluid reservoir. Be aware that it may take scores of lock-to-lock cycles to eliminate all of the air in the system.
If the air can’t be eliminated, then you probably have an opening in the system that’s allowing air to be sucked in as fast as you’re working it out.
For some reason more than a few Taurus steering racks have a loose nut on the passenger side that allows air to enter. Fluid normally comes out when this nut is loose but the fluid is captured by the rubber accordion-type boot at the end of the rack.
To get to this sometimes-loose nut, remove the passenger side wheel and use a flat screwdriver to pry up the metal clamp that secures the rubber boot to the inner part of the steering rack. Use a pair of pliers to loosen the smaller metal clamp on the other end of the boot that’s closer to the wheel. With both clamps loosened slide the boot off the rack and toward the wheel as far as possible. You’ll see a large round nut inside the end of the rack and this is the nut that may be loose. You’ll also see that the tie rod goes through the center of this nut, making it somewhat impossible to simply put a socket on it. There are four holes drilled into the face of the nut and there’s a special tool that goes around the tie rod, inserts into these four holes, and enables you to tighten the nut. In the very likely event that you don’t happen to have this special tool, you’ll have to fabricate something that securely inserts in the nut’s holes and allows you to tighten the nut.