Cadillac Seville / Cadillac Eldorado Forum Discussion, Possible power steering pump issue in Past Cadillac Vehicle Discussion; Hey guys, I have a 99 SLS. The problem is a whinnig/whiring noise from under the hood. It started as ...
Hey guys, I have a 99 SLS. The problem is a whinnig/whiring noise from under the hood. It started as the weather started getting cold here in Wisconsin. I hear it from the time I start the engine until it is turned off. The pitch/level is effected both the speed of the motor and turning off the steering wheel. Moving or not the noise is there. Checked the psf which was a bit low but nothing serious, add a few oz and the noise is no better. I am think power steering pump but not sure. If so, how difficult is it to replace and are there any super secrect tricks to make it easier? Thanks for the help!
A lot of GM cars have whining power steering pumps. If you get a new one it may still whine, especially if you get a re-manufactured pump.
It sounds like a power steering pump problem to me, but I'll let the others chime in as I'm not good at diagnosing.
If you do decide to change the pump, I think it's fairly straightforward (I changed mine on a '97 STS which may be different from a '99, but it was easy on a '97 -- only special thing I needed was a 6-in socket extender).
Others can give you more details -- or search, there are detailed posts about it -- but I'd wait for concrete diagnosis before jumping in and changing anything.
gscoot, you should invest in an auto-stethoscope ($10) and touch the probe end CAREFULLY on each component on belt train. Listen for the whining or whirring to become evident. It could also be your belt tensioner or idler. Then check the alternator. Don't forget to check the water pump and it's tensioner too (other side). If you still can't find it, Ranger has a cool trick...get a helper to put a breaker bar in the main tensioner and while you are in the running car, your helper CAREFULLY releases (pull back very slowly - hands away from the belt) the belt tension just enough to stop its movement. Did the noise go away? If so, it's got to be in one of your components on that train. Good luck - odd noises can be hard to find.
Another good way to diagnose this problem is to remove the serp. belt and spin each pulley with your hand. There is a good chance one will feel notchy or make a noise.
I learned this the hard way - Whining noise that changed pitch when turning the wheel to full lock
I figured this was a no brainer and changed the PS pump. When it didn't go away I tried spinning each pulley and I found A/C clutch bearing was bad. I pulled the clutch off (took minutes with a tool borrowed from Autozone). It was not the compressor bearings, but the bearing the clutch pulley freewheels on.
I was actually able to fix this for $25 - I couldn't find anyone who would sell me anything other than an entire compressor/clutch assy for $300 or so IIR, so I reinstalled and called a company called E.B Atmus in Springfield, MA. I read them the number off the bearing, and had a replacement a few days later.
You do need a shop press to R&R the bearing from the pulley, I just brought it over to my buddy's place.
I don't know if this is your problem or not, but somebody might find the info useful
Bringing back this old thread to say thanks! I believed the whining sound was from my power steering pump, and thought I confirmed that diagnosis with the stethoscope. But the pulley just below the pump turned out to be even noisier, and the real culprit! If it wasn't for this thread that I found in a search, I would have overspent hundreds and not have fixed the problem. The forum (and the search option) really works.