I have a issue with overly heavy steering. The first half turn in each direction is very stiff at slower speeds and the steering wheel does not return to center on its own, it stays stuck where it is until I turn it manually. I hear no obvious sounds or clunking coming from the engine bay or interior. The PS fluid level is ok. While searching it appears this could be cause by a number of things. 1) alignment 2) PS pump 3)Lower steering shaft 4) the steering rack Can anyone help suggest a way I can trouble shoot this on my own to narrow down list? What would be the best parts to start replacing first if nothing obvious stands out? Thanks in advance.