Power steering issue (rack worn out?)

[SilverS8]

Hi all.

I recently replaced all control arms except the tierod ends(as they seemed pretty good and the fact that it triggers a new wheel alignment)

All has been goo until the other day. Suddenly i have a "free" spot when turning the steeringwheel at standstil and low speeds. I can move the steeringwheel about 3-4cm without the wheels moving(or at least its minimal movment)

All control arms checked to rule out any loose parts.

To clarify:

-Engine off: Everything is solid, no slack/free spot
-Engine on and speed under 20 mph i can feel this free spot
-Over 30+ mph it all feels perfect.

I would think that f the rack is worn out i would feel the free spot when engine was off?

There is no noise,leaks or anything that would explain why this has suddenly happened.

Any info would be appreciated... Its MOT time within the next 3 weeks...

Jan