help me solve engine noise problem

blah!!! i did a system in my buddy's 02 civic coupe that consist of the new mid leval eclipse flip out dvd screen, with hide away brain, under the driver seat,(i forgot the exact model).  and a big db drive 120 by 4 amplifier. the noise is more of a wierd ticking sound at low volume rather than a winening noise, but the whine is their too. ive tried noise filters at the amp and they didnt make a difference. i unpluged the rca's at the amp and the noise goes away. i ran my own external audio signal into the amp and their was no noise, i even ran new high quality rca's across the back seat to the amp to see if maybe the rca's were picking up noise somewhere, and that still didnt work. i even check the battery to make sure there was no corrosion and the connections were good, and they seem fine.  What else can i try?? ive tried even running a return ground from the brain under the front driver seat to the amp itself and the noise is still their!! what could it possibly be??? it seems to be comming from the eclipse unit itself, but why is it so bad??? thanks.03 wrx stage 4

http://www.epanorama.net/documents/groundloop/basics.html You have a ground loop problem. See the excellent sticky on grounding problems. New Project: 2003 Pathfinder

I am fairly confident this is a grounding issue. New Project: 2003 Pathfinder

what are some test i can do to find the ground loop?? and also what can i do to prevent this?? will linking all the grounds to one point help me out?03 wrx stage 4

Yes, and probably a HU grounding issue, or maybe a bad engine ground strap.Support the12volt.com

try a ground loop isolator or a noise filter.

dangerranger96 wrote: are you sure that your power cable is not running any where near your rca cables, if it is it, move it to the other side of the car.  high quality shielded cables wouldnt completely get rid of this problem alone

i ran a extra set out side the car to test for this and it made no difference.

03 wrx stage 4

If you haven't already, read the sticky topic at the top of this forum about grounds.  You may want to post your question on Forbidden's ground thread.  Also, if you are using the factory wiring harness ground for your head unit, run a dedicated ground for it and see if that helps.Support the12volt.com