And it's not coming from Teh Basement h:


Anyways, noticed it tonight for the first time, and it's very peculiar. Coming from about the middle of the engine bay, I get a strange whine that's RPM dependent. It's doesn't fluctuate with the amount of throttle, as would an exhaust leak (Which was my first guess, due to the pitch of the noise), and is independent of the rotation speed of the wheels (Not a wheel bearing or something like that).

My car was warmed up when I first noticed it, so I don't think it's some random cold-start noise... and I certainly hope it isn't because of the oil level... I had it changed 2 days ago at the Honda dealership (I don't mind paying some guy $13 plus parts to change my oil... I hate putting my teggy up on jackstands).


I'm gonna do more troubleshooting tomorrow morning when the neighbors wont call the cops on me for revving my engine to 3K for a couple minutes... any trouble spots that I should look for that could cause an RPM dependent whine from inside the engine bay?

I actually think it might be my AC compressor... :dunno: any ideas?

 

Is your AC on when the whine occurs? Try turning it off while driving and tell me if it goes away. This could be a worn belt.

 

Y'know what? I sat down and recalled what I did when I started the car back up... and the AC was used to defrost the windows at idle for a minute, then I took off...

But the whine didn't sound any different with the AC on or off (Though, truth be told... I couldn't tell if the whine was still there over the AC system)... first thing I checked when I was driving...

I seriously hate AC on all but the most unbearable of days...

 

Some other potential sources:

Alternator shaft bearing?
Power Steering Pump?
:dunno:

 

The power steering pump is good... I know that

But the alternator shaft... good call... That's one part on my engine that I haven't really inspected since I got the car 20K mi ago...

Hrm... whine didn't show up this mornin... but it wont hurt to take out the alternator and inspect it :exnbp:

Man... I really _love_ troubleshooting weird intermittent noises...

 

If the bearings are worn... they can make an awful noise....Seems a little unlikely to me, but I'd just check to see that there isn't too much play on the shaft by grabbing hold of the pulley and pulling outward away from the alternator. If the shaft and pulley start to slide , then it may be time for new bearings, or a new alternator.
Otherwise, I'd check belt tension. ...:thinking:

Good luck.

 

I had some noises like that... took it to the dealer, and they had to tighten my accessory belts. I'd do that before you start pulling alternators, etc... Might also want to get some belt dressing.