Loss of power steering to left only

1997 pontiac grand prix gt… has loss of power steering to the left only. fluid level OK. turns right OK. ???

It probably is a failure in the rack. Either something has gotten into the valve spool that is keeping it from openning the pressure port or return port when the steeering wheel is cranked left or the rack outer pressure seal has failed on the left side. There is a secondary seal that keeps the hydraulic fluid from leaking out of the system which is only under return pressure so you will not see an external leak. In any case the rack will probably have to be replaced. You could do a pressure check on the pump, rack at right turn, and rack at left turn against resistance – just to be sure.

I agree 100%. The spool valve is the first thing that came to my feeble mind too.