09-07-11, 05:54 PM
I just picked up a 05 STS and i noticed while driving it home that When at a stand still or going really slow(like when parking) it is very hard to turn the wheel almost like there is no power steering. But when you start going it gets much easier. Then this morning it work just fine for the first couple slow turns then it got bad again. I checked the fluid and it is full to the top so there shouldnt be a leak anywere. There doesnt seem to be any noise coming from the steering either. The car does have aftermarket wheels and tires but they are the stock sizes there just high performance summer tires that are very sticky. So i dont know what to try next. Is it possible the power steering pump is bad and needs replaced?
Thanks in advance for any help you can provide.
The car is the V8 N* with 107000 miles if that helps
09-07-11, 11:30 PM
Update after driving it some more.........................
I does have a little humm to it when you turn the wheel and it hard. Also if i sit at a stand still and keep the car in neutral or park and rev the engine up to 2500rpm or higher it gets easier to turn and the noise goes away.
09-08-11, 06:50 AM
Powersteering Pump- Could be broken
Powersteering Hose- Possible that the PS fluid isn't getting through or being pinched on turns.
Rack and Pinion- usually occurs from an accident
Seems like someone had in accident in that STS a few times before you got it.
I recommend you take it to a dealer to Diagnose the problem for you for about $90.00. That would be your best choice.
09-08-11, 11:05 AM
100% power steering pump. Had to replace mine recently. Literally no power steering while at a stand still, but if you accelerate, it gets easier. You also will hear a whine of sorts as you turn and accelerate. You can find replacement pumps on ebay for around $100 or less. Make sure it is the right one for your vehicle tho. It is a PITA DIY project. If at all possible, get one with a pulley installed, otherwise you have to get a pulley extractor to pull yours off, which alone took me about half hour.
09-08-11, 10:01 PM
Well we looked it over tonight and the fluid didnt look so good so we went ahead and flushed it and put some lucas power steering treatment in it and it was a little better on the way home. So were ordering a replacement pump through advance auto and its only $85 with my fathers discount since he is a mechanic and buys everything from them. So were going to do that next week and hope that is all it is. Keeping the fingers crossed its not the rack too.
09-08-11, 11:35 PM
Couple tidbits to help you out. Below is a great mounting diagram for the 4.6.
The front bolt will have to come off with a wrench.(takes forever) since the pulley is in the way and the small nut on the back that holds the hose bracket looks simple, but is a huge PITA to get to. I had to use about 2ft of extensions and a knuckle to get it off. Ratchet almost to firewall.
Hopefully your new pump comes with a pulley. If not, you will have to use an extractor to pull the old one off since it is pressed on.
09-20-11, 07:07 PM
So we finally got the time to replace it and it fixed it. So it was just the pump and not the rack. A little advice if you have to do it your self. Take the left half of the airbox off and use a swivel socket and you can get to the back bolt very easy to take the bracket off which them makes the whole pump come out very easy. Once we realized that we could do it that was we did the complete swap in under 2 hours.
10-04-11, 11:55 PM
Ok so its been a couple weeks since i finished replacing the power steering pump and everything is good except for higher speed turning in corners. It still turns kinda hard compared to my 05 v6 sts. Is it possible that the rack is bad to? cause it turns fine at lower speed just like my other one.
10-05-11, 08:54 AM
My rack when south at 48k miles and had to be replaced but it was still covered under the factory warranty.
10-10-11, 04:32 PM
Anybody else know if the rack being bad would only affect higher speeds? because below 40 it is just fine its just when your at 50-70 and going around a corner it is hard to turn.
My 1SG has the ZF Steering (RPO NV7). It's noticebly harder to turn the wheel than my wife's 1SE.
02-28-12, 07:58 PM
Ok so it sucks to have to bring this back. :banghead::banghead::banghead::banghead::banghead:
So heres the story of what happened this time. I was driving and the message "service steering system" suddenly came up and i lost partial power steering and the "Speed limited to 142 mph" came up also. So i stopped at the next place i could turned the car off for a few minuets and started it back up. It ran fine for a few miles then i got the messages again. So everytime i would start it the PS would work for anywhere from 2min to 30min before i would get the message. Also if i used the remote start the steering would be fine untill i hit the actuall start button. Now after it doing that for a day or so when i start it now it immediatly comes up with that message. I do still have partial power steering just not full. It kinda feels like driving a large truck like our fire engine or tanker.
We already replaced the pump, rack, and steering actuator and everything was fine for almost 2 months. Untill two days ago when the above happened. It never came up when i was having the other problem so we figured its something electrical. But i had an extra rack and actuator so we took a couple hours and replaced them again just to see if that was the problem.
Unfortunately it didnt make the message go away or give me full power steering control and i still have limited power steering. I can tell its not completly gone its just not working comepletly. We have rulled out anything that it could me thats machanical with replacement so we are convinced its either the Steering position sensor, or the ECM from what others have experianced.
Does anyone else have any other thoughts on what it could be. I would bring it to the local dealer but i dont really trust them because they have had a few issues and the next closest one is 2 hours away. Any thoughts at all on how to fix it. I love the car but its really making me want to sell it.
Also i have been haveing a couple other small issues where the radio sometimes wont turn on and you have to restart the car. The seat and steering wheel sometimes go crazy when you first start the car and sometimes when you use remote start it wont let you in the car untill the 10 minuets is up or untill you use the key in the door. Those things are what is making me think it could be the ECM.
Thanks for any input.
Where's the next closest Cadillac dealer?