Is this a big deal?..

[Andy_Mac]

Not a mechanic so not really sure what sounds are ok on a car and what aren\'t.

I know in my trade (A/C and Refrig) a sound like this would generally indicate stuffed bearings which should be replaced asap

So i think this noise is coming from a pulley somewhere in the deep abyss.

I first noticed it as i was looking for the source of a high pitched whine that has come about since installing a decent audio setup.

It seems to only occur when the sounds turned up a reasonable amount and stops when the headunits turned off, maybe something to do with the alternator. Possibly a different problem though, thinking maybe wiring interference.

EDIT: Changed to youtube as photobucket compressed it and decided the possible bearing sound wasn\'t a necessary part of the audio...

[loner]

Sounds like a belt to me. Alternator or powered steering etc.

[titian]

yep belt slip by the sounds of it Or stuffed alternator bearing. i.e:- on the way out!

[ADIKT]

How much to change an alternator bearing ? Or do you need a new unit? Home job?

[Roo]

Bearings are $5-30 depending on what type it has.

Cost of the job depends on whether the brushes are worn when the sparky/you get in there. Brushes are cheap too like 10-20.

Most workshops will charge 1.5 hours and that will get it washed and rectifier/regulator tested as well.

[tebbyj]

If your talking about the high-pitched squeak sorta sound.

Mine seems to make it to, more so when cold so i\'m leaning towards a belt too...

[Codex]

If you go down belt path first may as well replace the A/C belt at the same time

[neodowd]

You can put candle wax on belts to stop them squeaking only works on belts that are not slipping

[Andy_Mac]

have now developed a high pitched whine that gets higher and louder with more things running (stereo, lights, a/c) and when engine rpm rises so i get the feeling the alternator is just struggling with the extra load from the stereo.

Can\'t get it to do it when it just sits there idling. Still makes the whine with the stereo volume turned right down which i\'m thinking would rule out interference running through the speakers, could be wrong but logically i\'d have thought with the volume right down a mild hum would be the most you\'d ever get. Stops when the stereo is turned off which turns off the amp so not sure what the draw would be from the amp with volume turned right down, might test that tomorrow.

Will take it for a drive with a passenger tomorrow so they can confirm whether it\'s coming through the speakers or not.

Sounds like a similar issue to this one, never posted up what fixed it in the end though..

http://www.clubsub.org.nz/forum/index.php/topic,19430.0.html

[Andy_Mac]

thinking about it A/C shouldn\'t really effect it as its a different belt straight off the engine..

maybe a/c fan draw i guess..

[Marky]

So it\'s electrical interference then, stereo off stopping the noise is a pretty good indicator. Is it a suuuuuoer high pitched squeak which rises with rpm?

I had this problem years back - I think it\'s a grounding thing? - you can just get isolator / filter type things if in doubt

Might be as simple as a power cable running alongside something stereo related

[Andy_Mac]

yea really high and rises with rpm.

i\'ll have a proper listen to the speakers tomorrow and check the amp ground.

[Fastfour]

Are you running all your amp leads together from your stereo to the amp? If so that could cause it. Move the power wire away from the RCA lead and that should do it. I always ran power down the transmission tunnel and RCA lead down the left sill.

[Andy_Mac]

Na rca\'s run down the driver side and amp power down the passenger side

[Andy_Mac]

Amp ground wire had a slightly loose crimp so redid that crimp. Hasn\'t made any difference to the noise. Next step will be trying it running with one speaker running at a time as i can\'t really hear it through them when driving

[nickmcgill]

This is why I got mine installed by a professional

[Andy_Mac]

Yea starting to think i may do the same next time..

[tma]

Got a similar issue here. The two options I\'ve figured are:

* Attempt to clean up the audio on the way to the amp via a group-loop isolator. This is a bit of a cludge job, will work somewhat and may reduce a bit of audio quality - but it\'s braindead simple to throw in.

* Clean the 12VDC+ line coming to the head unit (tablet in my case) via a car noise filter. You can buy them or build your own.

[Andy_Mac]

Finally got a result!

Pulled the left door card off to get closer to the speaker and Found the sound is coming through the front door speakers. so plan is to run the wiring further away from the amp power and hopfully that fixes it.