noise!

[nathan0711]

i have a big problem and im hoping someone here may be able to help. i have an install in my car consisting of a sub, 2 amps, a pair of 6by9's, and the door speakers and a pioneer headunit. i have recently rewired the entire system and replaced one of the amps and the headunit, the power and the remote wires run down the nearside door trim, the speaker cables run down the offside trim and the 3 rca's run down the handbrake/geargaiter trim area. anyway since rewiring and adding the amp i have an annoying high pitched noise that works with the engine, the high pitched noise changes with the engine, rev the engine the noise revs, turn on the heater this comes through too. its got me stumped to be honest. ive had the alternator belt off and started it, this made no difference it was still there, ive tried unpluging the headunit and trying a different one this made no difference, i just wondered if there could be a fault on the cars wiring that someone may know about. any help would be greatlt appreciated. thanks, nathan

 

[R1ch85]

Well it sounds like alternator whine, but I'm guessing you already knew that since you've checked the alternator belt..

Check all your earth points, or failing that, if you have any spare power cable you could try upgrading the battery negative to chassis wire.

 

[nathan0711]

ruled alternator out mate, had it completely disconnected and it didnt make any odds. checked all earths given everything its own earth. its a really annoying fault. thanks for the ideas tho mate

 

[truss]

Its your headunit mate. pioneers are prone to this. its on something called earth track in the unit. basically, your ground points weren't solid enough so your amps were partially grounding through your RCA's to the headunit. the earth tracks on the pioneers are terrible.
I'd get that tested.
edit:http://www.talkaudio.co.uk/vbb/search.php?searchid=6423858
have a read through that. it helped me a few years ago.