Been real perplexing to me, trying to help a lady out. Hope I'm posting in the right place as I'm new here.
The lady had no steering assist at low (idle) rpm. I read the forum and cleaned the throttle plate, but only gained 50 rpm. Helped a little. So I flushed her old fluid out and removed a reservoir full of the new fluid. I then added 12 oz. or so of Lucas power steering stop leak to improve the viscosity and topped it up with new synthetic power steering fluid.It actually steers like new(has 250K miles on it) at a low idle. Just passing this on. Hope it may help someone.