I have a constant whine coming from the power steering pump when the car is on. If the RPMS rise, the whine rises. I used a stethoscope and it's def coming from the power steering pump. Couldn't find any leaks and wasn't low on Power steering fluid. I tried bleeding the pump and I pretty much constantly get big bubbles. So cars off, have the reservoir cap off, and turn the wheel left and right to full lock. The fluid in the reservoir will go up and then go down with a couple of bubbles surfacing in the reservoir. After doing this, I don't have to add any fluid in the reservoir when that happens.

I replaced the seals on the pump, no change. Got a new remanufactured pump and installed it, still same exact noise. I took the serpentine belt off just to be 100% if was from the pump, and no noise when I started the car. At this point i'm pretty stumped. My guess is that it has to maybe be one of the power steering lines is sucking in air, but not leaking somehow? Anywho, was looking for some insight or things to check/try.

 

Added video

 

cant tell from the video. have you tried wetting the belt? I dont know but something I would try

 

I had the same thing last year. I also had the power steering fluid look very aerated after an AutoX run even with vacuum bleeding it right before the event. I bought a new OEM pump which of course fixed it. I dont know if theirs a rebuild kit, but would be nice to rebuild my old one as a backup.

 

Alright it isn’t the power steering pump, good thing I replaced it LOL 🥴. So I threw on a new serpentine belt, same thing. I got my stethoscope again and I checked the power steering pump and it was the loudest source, until I checked the ac compressor…. Def more of the noise is coming from that, so I think I found the culprit, but at this point gotta search the forums to see if anyone has had the same symptoms and what to replace.

The Evo has like 130,000ish miles and I’ve never done anything with the AC, so not sure exactly what to attempt first. Also the pulley seemed to spin fine by hand. No grinding or much play, also no extra noise when AC is on and the ac still blows
cold air.

 

If you have replaced the timming belt it can make a squealing sound. On my 9 it does it when cold. The belt rubs the crank timming wheels very slightly.

With the car cold, remove the serpentine belt and start the car, you can run it briefly this way. If you hear the noise it is the timming belt. Fix is to ignore it or change the right side casting to a revised one that shifts the belt path slightly. Search and there are threads on this. Not sure if the parts are still available.

 

Maybe a dumb question but, you are using a new serpentine belt during this whole thing, right?


Edit: Never mind, missed you saying that you did replace the belt. You can grab a smaller belt to bypass the a/c compressor and see if that helps. You can find the correct belt size / part numbers if you search the site.

 

you could buy an extra tensioner and test it out, its not bad to have a backup. same for an ac compressor at that age. I just have harborfreight AC vacuum pump/gauges and have learned to service several cars. refrigerants are cheap if you buy bulk from Sam's Club

 

I thought my tensioner was the problem as well when I had the whine. I the bearing in my tensioner was definitely bad but you can order just the bearing itself to replace. Didnt change the noise I had though, in my case it was definitely the PS Pump. I dont have AC to worry about though.

 

IIRC i broke the thing to unwind the tensioner, so its good to have the whole thing as backup

 

At this point its probably good to have like 1 of everything as a spare

 

true. i hate downtime when stress-relief weekend racing is needed

 

Im 96% sure I figured the problem out, it's the idler pulley on the serpentine. My stethoscope has an extension where its basically like the screw driver method putting it against stuff. Putting it against the idler pulley(since the center part doesn't spin) and it amplified the same exact sound to the max. Surely this is it, surely..

Noting it's a Gates Idler pulley. Replaced that when I did my timing belt about 3 years ago. It has around 10k miles on it. Guess I'll buy oem.

 

My wife's benz melts those idler pulleys(plastic) and then the shredded belt gets coiled up behind the crank pulley pushing the seals in leaking oil. after that, stranding you somewhere with no acc belt. Luckily our evos aren't that crappy. I dont mind replacing that pulley every few years if it gives some noise way before it goes. I like new shiny OE parts lol

 

It was going to be my race weekend 🥲. Anywho thanks for all the replies everyone.