Power Steering Issue

I have a 2003 Kia Sedona but I think that this is probably a general power steering question. I had a new tire installed and had my full size spare tire switched onto the car as well so that I didn’t have to buy a replacement for another of the tires that was worn.
Up until this simple tire change I had no problem with the power steering. About a day or so later I noticed that the car became difficult to steer. While going straight it seemed to work just fine and the steering wheel felt normal. However when making a turn to either the left or right it is a different story. The wheel is very difficult to turn and its a herky jerky type of resistance, not a constant strain like an older car without power steering would have.
I checked the power steering fluid and it is at the correct level, so no apparent leak.
One day last week as a matter of fact the steering went back to normal for two days, only to be followed by a return to the steering trouble again.
Does anyone have any idea what the problem might be?

Did they check or refill any fluids?
Check to see if something was spilled on the serpentine belt.
Is it the original 11+ y.o. belt?
Might be coincidence that it needs changing.
Just removing wheels doesn’t directly affect the steering, unless the work was done by a trained gorilla.

They just changed the tires. No other work. and the fluid reservoir had not been disturbed and is not leaking.
The belt is the original as far as I know. What other causes might there be? Aside from the belt?

If it isn’t the belt slipping, you need a new rack.

I’d replace the serpentine belt and tensioner first. I’d also use the turkey baster method to change the power steering fluid. 11 years is probably long enough for them. Altogether, this will be a lot cheaper than a replacement rack.

Is this an awd ie 4wd car? if so, your tires may not be of equal diameter causing issues. one generally rotates tires, and throwing in the unused spare could be the problem.

It’s front wheel drive

“If it isn’t the belt slipping, you need a new rack”

As I recall, the steering rack was one of the weak areas on this model.

Before springing for a new rack, ask if your shop has a pair of known good tires they could install temporarily to see if that fixed the problem.

If you put an 11 year old spare on the front, that’s probably the problem. It’s also dangefous. I think you should put 2 new tires on the front and see what happens.