Hoping for some help here guys. Took my 1995 S1 2.8 SWB PE8W into a reputable mechanic (CVI) a few weeks back to diagnose my steering woes. They included a notchy lumpy feeling and at time stiffness when cornering. Along with that the steering wheel would jerk back or need assistance returning to centre. There was a noticeable pull to the left where there was none before. After taking a good look at the front end and tightening a slightly loose tie rod end the mechanic had no other explanation other than it "could" be the steering rack. I have no leaks or anything obvious. He suggested a good fluid flush, hoping that it would clean something out and come good. There was a slight improvement but not great like it was. Some of of lumpiness had gone but the stiffness was still there.
Then, a week or so later, suddenly out of nowhere it was REALLY good. Just like normal! As you can imagine i was stoked. It didn't last long though.. maybe two days before becoming stiff again.

Any thoughts on this? Could it still be the rack if it came good like that? Did something in the power steering box start working again? All of this happened when the cold snap started this winter..not sure if that would have anything to do with it.
Thanks in advance!