Help with handling?

NoHyperbole

Regarding tightening the rack and pinion nut, I too have a 2014 coupe and was experiencing "loose" steering, as evidended by the steering wheel doing a quick left-right-left-right shimmy when I hit bumps in the road that affected only one front wheel.

I brought the car to the dealership, and the tech tightened that nut about one full turn. That made an immediate huge difference in steering feel. On-center feel was much more pronounced, and the steering generally had more heft and resisted the aforementioned shimmy. HOWEVER, the steering would no longer self-center when making a turn; I had to manually guide the wheel all the way back to center. So I returned to the dealership and had them loosen the nut 3/4 turn, which cured the new problem and caused the old problem to return.

I spoke to a Nissan master tech who works at an independent shop, and he said never to tighten that nut, as it casuses the gears in the steering to bind, which is obviously detrimental long-term. So yes, this is yet another case of a dealership's service department not knowing its products well enough to implement the proper solution, which in this case may be replacement of the steering rack.

Jhill

Sounds like your dealer is like all the others around here (not just nissan). All dealers are hiring cheap labor now as more and more techs leave the field for better/higher paying jobs, probably why your master tech is no longer at the dealer. Yes he is correct that you can do damage and bind the rack and pinion is misadjusted. A good general rule is to turn the rack one way or the other and then adjust the adjuster until it just touches and then back off 1/2 turn. This will ensure you have clearence and will not bind. It is not unusual for a rack to have more play in the center as that is where the rack stays 99% of its life so the west becomes uneven.

There is a chart for allowable steering wheel play based on wheel diameter but it is pretty loose in my opinion (somewhere around the 2inch mark) where I have never really seen a rack and pinion get that loose without some very serious knocking or worn parts. I think that chart is more for linkage and gear box steering.