My 93 acura legend is hard to steer on city streets at 20 mph. no noise. I have checked for correct fluid level. Also insured proper tire pressure.

Check the outer tie-rod ends and upper and lower ball joints. The grease may be gone and the joints are shot and need replacing. Go with Moog parts.

If you haven't periodically changed the fluid, and the problem persists, the pump or rack may have failed. This is not even scheduled maintenance in the Owner's Manual--common sense tells you to do it. I do a partial change every 3 years in my Honda. In your case, follow the Service Manual's approach to completely changing the power steering fluid. This will help you assess the power of the pump and allow you to really check the condition of the fluid. If the problem persists, the rack will likely need replacing.

My gut is you need to replace the outer tie-rod ends and ball joints.