High Pitch Sound (500 To 1k Hz) From Alternator?

[Eric Cheung]

I notice a high pitched continuous sound from the alternator. The frequency of the sound increases with engine revolution. It is about 500 to 1000 Hz during idling (660 rpm), higher when the a/c is engaged (about 1000 rpm). I stepped on the gas pedal to increse the engine revolution up to 2000 rpm and the frequency of sound increased with engine rev.

I checked the belts and the tension was tight enough. I think it is the alternator. Or is it something else?

Any advise is highly appreciated.

[SKperformance]

need to have the bearings checked

[DBrucher]

Mine does the same kind of whine, but I only notice it during startup/warmup. I actually listen for it to know if my auto-start works in the AM (I park around the corner).

[SKperformance]

My power steering pump bearing went and cause dthe same noise problem also.

[Eric Cheung]

Is it the altnernator or powersteering pump in my case?

I touched the tip of a 10" long screwdriver on the alternator and listened at the end of the screwdriver plastic handle, the sound was amplified and was very noticeable. I did the same for the timing belt cover and other metallic parts and the sound was not very noticeable. From this I think it is the alternator, am I right?

[Eric Cheung]

Ok I spayed some silicone lubricant to lube the alternator axle/bearing. Now the high pitch sound it hardly noticeable. However, there is still a lower pitch sound going on which also changes with engine revolution. Maybe the power steering pump is about to go?

[NeiLtYmE]

i recently swapped my alternator. Since then I've also been getting this same noise you are talking about. Its not so bad, but I can notice it. Coincidently I was told my power steering pump was going bad a few months back. The noise only started right after i replaced the alternator. So I am assuming its coming from the alternator.

Let us know what you find out.