Slight Whining Noise coming from engine bay during acceleration

[samdajellybeenie14]

There is a very slight whining noise that sounds almost like a tiny supercharger coming from my engine bay when accelerating. I used to like it but now it's just getting annoying. It seems to only happen when I get up near or above 2000 rpms. The last time I heard it, I stopped and turned off the car, and then restarted it, accelerated and the noise wasn't there. Any ideas of what it could be? I have a 2002 sport w/ 144,000 miles.

 

[LittleCaesar]

Nope, but I would suggest putting the car in idle, opening the hood while someone else revs the engine past 2000 rpms and see if you can hear it. I'd guess a bearing of some sort. How old are the belts?

 

[Jon]

Most likely the alternator or could just be low on PS fluid. But the alternator is pretty much the only thing that will give a "supercharger whine" whereas everything else usually squeals.

Suggestion: take off one belt at a time, process of elimination man!

 

[Blanco]

My 'whine' was very similar but then became more metallic sounding over time. It seemed that it was down to something worn in my A/C compressor (clutch?). Pretty sure they can be repaired or rebuilt but I lucked out and found one in a parts yard cheap so just replaced it outright - no more whine and better performing A/C. Might not be your problem but worth checking out - try and get a long stick down onto it and put the other end up to your ear, you'll hear it right away if there's a problem.

 

[ogden8]

Perhaps the water pump pulley. When is the last timing belt change? I am asking this based off watching this video btw...go to 5:15, it demonstrates the sound of a water pump with damaged bearings.

Toyota timing belt - YouTube

 

[samdajellybeenie14]

Perhaps the water pump pulley. When is the last timing belt change? I am asking this based off watching this video btw...go to 5:15, it demonstrates the sound of a water pump with damaged bearings.

Toyota timing belt - YouTube

The timing belt was replaced at 125K miles and it has 144K miles. Even so, I'll check out that video and hit you back.

 

[samdajellybeenie14]

Most likely the alternator or could just be low on PS fluid. But the alternator is pretty much the only thing that will give a "supercharger whine" whereas everything else usually squeals.

Suggestion: take off one belt at a time, process of elimination man!

I know this might sound a little stupid, but what would be wrong with alternator if it sounds like a SC? Is it going bad? I'll check the PS fluid right now...

 

[kao]

Sorry for necroposting. But i've got the same issue:
whining noise from engine bay about 2000 rpms and above.
I replaced all of bearings include alternators' but noise still there.
Today I've started engine without drive belt and ... noise still there.

So possible reason somewhere in engine. Maybe air filter or throttle.
Anybody faced such trouble since the first posting?

Sorry twice, for wrong thread(