1998 Civic EX whistling noise
 

hey everyone, just bought a 98 civic ex

and now i'm noticing this intermittent whistling noise while driving. it only stays for 4-5 seconds and goes away. and then comes back maybe 20-30 seconds later. it also seems that if i let off the gas, or give it more gas, it seems to go away quicker.

it sounds like its coming directly in front of the driver under the hood somewhere, i havent been able to open the hood and see if i can hear the sound. it also happened when idling the other day.

i'm thinking maybe the alternator belt needs to be replaced, any thoughts?

the belt doesn't make that noise. either its alternator whine which would change tone as you accelerate, or it could be something else like transmission or ps pump.

Yeah have a look at the ps pump.

the sound does change pitch as i accelerate, it goes higer, and then disappears

by ps pump, i assume you mean power steering pump?

yea but if it changes pitch its most likely the alternator. maybe the bearings going out. or it could be noise going to the speakers. does it do this with the stereo off too?

yeah, i tried turning everything off, the radio, and the fan and stuff, so its gotta be coming from under the hood

do you have an intake? my friend's '96 civic does the same thing. i think its the VTEC.

but that only whistles above 3k rpms. not during idle.

no intake, everything in the car is stock as far as i know

it seems to have gone away since i ran the a/c for a bit, so we'll see if that fixed it