Hi all,

I've recently noticed that my factory alternator on my TPI engine emits a high pitch squeal when the ignition is in accessories mode, but engine not running. I can't hear it when the engine's going, probably due to engine noise. Should my alternator be making such a noise or should I get it checked out? I did have the alternator rebuilt 300 or so miles ago and the voltage output seems fine.

 

I believe mine does it also, but its not a squeal.
Its a High frequency buzzing of some sort

But, I can only hear it when the hood is up, and working
under the hood or around the engine.. And it only does it
when its 1/2 key turn or accessory mode like you said.

If you can hear it 10ft away with the hood closed, then
that's not normal in my opinion.. or even inside the car
with the engine off

 

Cheers for that. By the sounds of it I've nothing to worry about. You're right, it's more of a high frequency thing than a squeal. Do you know what it is in the alternator that makes the sound? I'm just curious more than anything.