A couple years and many miles ago, I was driving the xk8 under 55 degrees outside temp, and every time I "moved" the steering wheel I would hear a higher pitch cat like purring sound. The noise would go away when I stopped "moving" the wheel. Now today, it was about 80 degrees outside and the cat purring is back - only when steering wheel is "moving" left or right and gone when the steering wheel is not moving; even if I was stopped in park, any movement of the steering wheel would produce a sound, but holding the steering wheel still, in any position, stops the sound. The purring is coming from the steering wheel, not the serpentine belt (new) or the power steering pump (recently flushed). It did go away later in the day...

???

 

Check the PS fluid level. I had an Audi the did that and turned out it had a leaking PS hose.

 

Classic low fluid symptoms.

 

What could possibly be wrong with a Jag Purring like a cat?

 

I just checked the fluid and it's fill right up to the top line. I know that fluid over that top line is considered over-filled. Sound is gone for now, but I know it will be back.... What should I look for when it does come back? There is no fluid leaks I can see, and fluid has always been good. Maybe it's the power-steering pump? At first, I thought, maybe a dried-up and/or defective bushing or spacer in the steering column, because sound is more coming from the steering wheel than the pump, but...???

 

With the car running and the hood open, have an assistant turn the wheel while you listen to the pump area. Do you hear it when the wheel is turned right and left? A worn pump can sound a bit like low fluid.

 

I have seen nearly seized lower steering shaft U joints on these cars. You have to look for rust dust at the U joints themselves. I’ve also heard the steering shaft bushing make weird sounds. The lower steering shaft where it goes through the firewall, there’s a bushing in the middle that can make noises. Perhaps use some spray lube with the wand still attached to it to see if you can get anywhere with it.