Lost my power steering after driving 2 mts. Pulled over and it was still stiff but worked after another minute. Drove a total of 4 miles with no problem. I checked the power steering fluid and that was fine. Also the belts felt fine. This was after a night of heavy rain so I’m not sure if that could have caused the problem, but it has never happened before.
The only thing I can suggest is a stretched drive belt slipping on the wet PS pump pulley, perhaps exascerbated by a week tensioner (if it’s a serpentine belt).
If the belt is just a LITTLE loose or worn, it can slip badly when wet…