2003 V70 Whiny noise from engine at low gears

[f97ao]

Hi,
I bought a V70 from 2003 a few weeks ago and from what I could see everything was in order, good service history and drove well etc.

But now when I'm driving I hear a low high pitched "whine" on the low gears.
- It sounds very synthetic, almost like a police syren. "eeeeeeeee"
- the pitch changes when I switch gear. I only hear it when driving on the first or second gear.
- the volume is very low, but its audible. If I had the radio on I don't think I would hear it at all.
- I mostly hear it when the car has been cold, it seems to go away when the engine gets warm.

Does anyone know what this could be?
Thanks,
Andreas

[abscate]

Search under the hood with a garden hose and listen for the power steering pump and alternator bearing at idle. Have some one lightly rev the motor while you do this.

I'm guessing its a engine speed related noise that you can hear at higher car speeds and not related to the transmission speed.

[vtl]

First guess is serpentine belt tensioner. Its bearing dries out faster than anything else sitting under same belt. Tensioner is somewhat expensive, but you can replace only pulley with bearing, was like $20 for me.