Some 2000 km I replaced the power steering rack/device underneath the car as it started leaking fluid with another used rack.

The car steered heavier but not too bad but now a few thousand km further it's seems to get worse and also note that the steering wheel does not automatically come back after coming out of a curve i.e. it seems to be stuck in it's position.

Also the cars steers slowly to the left altough allingment has been checked 3 times and is correct.

What is the problem here and could there be a connection between the two problems?

Tnks!