Seeking some guidance again from this awesome online community. This time it’s my wife’s car - 2005 Mazda 6, 4-cyl engine, 143,000 miles. Serpentine belt started making a horrible whining noise, got much louder and whinier when turning the steering wheel. I added a moderate amount of power steering fluid to bring the reservoir to full, I’m guessing 1/8 of a bottle. Made no difference in the noise. I got under the car today and there is definitely a power steering fluid leak. Oil and transmission plugs and pans are bone dry, but there was oily fluid caught in the plastic cover you have to remove to access anything underneath the car. At first I suspected the steering pump was leaking, as there was more fluid on that side than the other. But, then I checked the frame the runs underneath the rack. There was fluid along the top side of the frame, on the same side where I had observed the power steering fluid inside the plastic vanity cover.
So, I now suspect a leaking rack, causing low fluid levels, causing the pump to go bad as well. Is there any other likely scenario? I do wonder how a loss of only 1/8 of a bottle of steering fluid could cause the pump to fail. Any other things I can check to narrow things down? And, is there any kind of “stop leak” substance I could try, without running the risk of mucking things up inside the rack, as radiator stop leak substances sometimes do to cooling systems?
And, if this is both a leaking rack and failing pump, does it make a difference which I replace first? The pump is within my mechanical abilities, but the rack is probably more than I could handle on my own.
OP here . . . re: the serpentine belt, I should have added that it’s less than two years old. And, I did try to totally eliminate the belt as a possibility by running the AC to see if the belt noise would increase when the compressor engaged. The belt noise didn’t change when the AC was running. So, from what I can tell, that makes the case for a bad steering pump stronger.
I presume the PS pump is on the serpentine belt path on the vehicle; so you are thinking the problem is the PS pump b/c the noise increases when you turn the steering wheel. That’s a reasonable guess. But it is also possible the noise isn’t related to the PS pump at all. Small PS fluid leaks are pretty common and mostly innocuous as long as the fluid is kept topped off. I have to add a little PS fluid on my Corolla every couple of years or so. So the noise could be something else, and turning the steering wheel increases the tension on the serpentine belt, which causes whatever the problem part is on the belt path to make more noise. The various idler pulleys and the belt tensioner are common candidates.
As an example of how it is easy to guess wrong, I had a whining noise on my Corolla a year or so ago, when the engine was cold, seemed to be related to turning the steering wheel, and I fixed it by simply tightening the alternator belt. And the way my Corolla is configured, there’s no serpentine belt. The alternator belt is a separate belt from the power steering belt. Turning the steering wheel puts add’l rotational forces on the PS belt, and that somehow affected the alternator belt.
I also am not sure that the PS fluid is actually leaking. The OP had some low level, topped it off, but I don’t see a real major leak being mentioned. If there is some seepage, I would just patch it up to normal aging. I am just going by the info provided.
On a similar note, it is interesting how different people read the same story but come to different conclusion. This has been studied and it is based on our inherent “bias”. We interpret things based on our life experiences. In this case, my view might be based on the fact that every time I have had a similar problem, it has been something other than the PS.