I bought this new(to me) 98 Volvo s90 with 98k miles. Now that I've had it for about a week now the whining is starting to become bothersome.

A sound that seems to be coming from around the power steering pump. The initial sound will fade away once the car has been running for a while. But the whining persists when I accelerate. It sounds like a belt type whine. I've uploaded a video I took this evening of the car to help better describe the sound.

https://www.youtube.com/watch?v=pen7...ature=youtu.be

 

Are there any ideas as to what could be causing this noise? It seems to be focused in the power steering pump. The belts all appear to be fine and in good shape. I'm out of ideas as to what it could be.

 

Could be the pulleys/idler wheels associating with the timing belt or accessory belt. Did you check the fluid levels on the power steering reservoir and look for any leaks etc? Does the noise change when turning at low speed (ie turning around in a driveway etc)?

Next step would be to remove the drive belt and turn the idlers by hand to see if anything feels "off" or has noise.

 

Well my first thought was that there was an issue with the powersteering seeing as the noise seems to definitely be in the area. The fluid is at a good level and there's no obvious leaks in or around the area. There also hasn't been any sort of increase in the noise when I'm turning to lock at low speed or any sort of loss of power steering. Which is why I was flabbergasted by the noise hah. My plan is dig into it this weekend. I appreciate the input very much,
thanks!

 

I'm having the exact same issue with my 98 v90. Did you find a solution?

 

try pulling the oil dipstick just a bit and see if the sound goes away

 

I'll try that when I can get someone to start it for me. it goes away to quickly to do it myself.
I watched bushwack's youtube link after i posted. its not the same.

it seems to be coming from the back of the engine under the valve cover.

I fear I may have to pull a camshaft or it's an oil pressure issue.

Can you tell me what your test can tell me before i try it?

 

it squeals at start up for a few seconds and does it again much more quietly the first one or two times i accelerate then runs fine.

does it everytime regardless of engine temp even if I shut it off for only a few seconds.

 

then it wont be the whining noise of it having too much vacuum. So the dip stick pull isnt necessary. so you can rule that out.

 

I had a similar issue with my 98 S90 when I bought it. It sounds like something is not getting lubricated for a few minutes, almost as if there is a loose fan belt inside the valve cover. I added a can of SeaFoam to the oil, and ran the engine for 6 minutes with it in, revving it a few times. I then allowed it to cool down, and changed only the engine oil filter to a new Mobil 1 filter and ran it again for about 5 minutes. After allowing it to cool off, I drained the oil, allowing it to completely drain out for an hour, and also removed and replaced the oil filter again. I added 4.5 quarts of Mobil 1 5W30 synthetic and a quart of Slick50 Oil treatment. I drove the car for 30 minutes at city and highway speeds. The noise is gone, and has not reappeared for 2k miles. I do not know the condition of your particular engine, if this will work for you or not, but I can say that this is the second engine I have eliminated noises and revived with SeaFoam and Slick50.

 

Check the belt pulleys, for both serpentine and cam belts. If they whine when cold, they will shortly fail and that would be fatal for the cam belt.