2007 Yaris strange engine bay related noise wtf?

[GoodAsGoldYaris]

https://www.youtube.com/watch?v=H34oiVCICig

Any ideas on next steps? Could it be the alternator? It's a consistent noise these days, apart from the droning noise it doesn't seem to have affected anything else.

[CoryM]

Definitely rotating noise. Remove the belt and spin/rock your water pump pulley. It may the impeller hitting the block or a bad bearing. It also kind of sounds like a diode problem in the alternator, so it could be that or an alternator bearing. You can also use a stethoscope (or a long screwdriver to your ear) to pinpoint the sound, but I bet it will be obvious once the belt is off.

It could also be timing chain, but not very likely. If you start the engine with the belt off and the noise is still there, it's timing chain.

Cheers.

[Exiwolfman]

alternator but also look at water pump...from the sound i would say alt.

[jra]

While you are checking the water pump and Alt. check the crankshaft pulley, sometimes they separate from from the hub and rub the timing chain cover.