hey I have a 2007 Grand Prix gxp I started having power steering issues while only turning left I assumed it was tie rods I replaced inner and outer on both sides still had the problem. got a reman rack and pinion changed it still had the problem. went to another parts store and got a different brand reman rack and pinion still having problem. I did the same thing for the power steering pump bought a reman didn't fix problem so I bought another reman from a different parts store still having problem. I replace power steering pressure and return line cv axles on both sides I replaced driver side hub bearing control arms and sway bar links fairly new and show no physical signs of wear. the car is throwing codes for my MAP sensor a code for my brake switch circuit and a code for my tap shift. no other codes and CEL is not illuminated. any suggestions? again car power steering barely works when turning left ability to turn left does improve when I press gas. turning right is perfectly fine
So the rack is bad. And you shotgunned parts. Oof. Get a warrenty on the rack and pinion? Hard turning left means that's bad rack. If it's stiff both ways it indicates pump. Considering you practically replaced everything, has the system be properly bled? Do that first. If not then a warrenty is in order for a new rack. Feels bad if that be the case.
I don't think its the rack this is my fourth one. also my 3 power steering pump. possible relay or fuse?
Unlikely, if it is I'll be surprised if it is the fuse for sure. Since if the fuse blows then it shouldn't work at all. To my knowledge there is no relay for the P/S on the grand prix and is just driven by the pump via belt, at least for mine the 2001 model. Has the system been bled proper? Hear any noise when turning hard left (full lock?) I would say it is more likely that a gritty fluid or bad hoses be the case. But considering the pump and rack has been replaced multiple times I would like to assume that it has been done proper. Try another shop to seek a diag perhaps. Had the belt been replaced? A loose belt could also be cause. That being said, You can Google to see where the fuse and relays are for your model. If it does you can easily test the relay by swapping I out with another. If you swapped it and your P/S miraculously works then it is that indeed. Good luck.