Need help with 'whizzing' sound tied to RPM (video)

[usapadyra]

I'm trying to figure out what this 'whizzing' sound is. Wondering if anyone has ever heard anything like it?

Best I can describe it's a kind of soft buzzing / whizzing tone, linked directly to engine speed. It's not exactly a whine, at least, I've watched 100 videos demonstrating different whines and none of them sound like what I've got going on.

Doesn't occur when cold. Doesn't start as soon as engine is up to operating temp - takes a bit more driving than that for it to start.

Happens in Park / Neutral and in gear while driving.

I'm hesitant to pull the serpentine belt and eliminate those components since it only occurs when hot, and I don't know if it's OK to startup from hot without the water pump running. I also notice that if the car is sat for only 10 minutes it won't immediately return upon restart, so I don't know if I can get the air tube off, serpentine belt off and airtube back on fast enough to be sure it hasn't just cooled down in that time.

 

[usapadyra]

Just in case - here it is again with the audio EQed so the sound is much more prominent over the engine noise:



Cheers

 

[donalds]

I can't hear anything wrong
Lots of fan

 

[cober]

I presume it's power steering pump

 

[usapadyra]

I presume it's power steering pump

I did wonder that. The start of the noise did coincide with me adding a bunch of Prestone generic PS fluid. I've since found out that this PS system really just wants Mercon / Mercon V. I've been gradually flushing the Prestone out using the turkey baster and re-adding method. Only thing is, the noise does not change at all when turning the wheel. I don't know if this is relevant.

At the time I also had a new alternator and battery installed after the old one failed. On top of that, I was also refreshing / improving the trans fluid (via the dipstick extract and re-fill method) after a trans service.

So there were a few things changing around the time I first noticed the noise.

Someone on another forum had a simple idea - to use one of those laser temperature guns when the noise is present and check the temperature of the pulleys and components running off the serpentine belt. My friend has one of those temp guns so I'll give that a go and see what I find.