2001 V70 2.4T, 266K miles:

I'm looking for ideas on a symptom the car has developed.

A few months ago I began noticing a high-pitched whine. It has remained, maybe getting worse, maybe not. I'm used to it now...

It is dependent only on engine speed. Not vehicle speed, doesn't matter what gear, park, or neutral. Also doesn't appear to be dependent of engine load. Noise occurs all the time, hot or cold.

I replaced the serpentine belt and tensioner pulley because it was quick and easy. Bearing was funky, but no change, was able to observe the other accessories. No radial play in PS pump, alternator, or AC compressor and they spin freely.

My next step is a water pump, t-belt and pulley/tensioner. But should I be looking towards a turbo or something else? I was hoping to rule out turbo since the sound doesn't change with engine load.

TIA

Try using a piece of heater hose with one end held up to your ear and the other end poking around the accessories and listen for noises.

Start the car without the serp belt and listen.

And just why didn't I think of that? Finally stopped raining here, pulled the belt off the crank and Voila! no more whine. Now I'm not sure which accessory to go after...

Thanks for your help.
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V70 / Mini

Don't forget the idler roller, that would be a prime suspect.

Idler roller is new. That was the first step since the bearing in it was obviously worn out.

Upon further review, I believe the noise is coming from the AC compressor pulley. Up close it sounds like a bucket of bolts, changes when the clutch engages the compressor.

Now to figure out what route to take to replace it.

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V70 / Mini

Packing new bearings is not easy, so here is a link for a new clutch:
http://www.ebay.com/itm/New-AC-Compressor-COMPLETE-CLUTCH-Assembly-Fits-Volvo-V70-2001-2002-A-C-/221438177525?_trksid=p2141725.m3641.l6368

Who knows if it is any good, but appears to be cost effective.
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My back feels better when I sit in a Volvo seat