My problem has been going on for quite some time and I've been beating my head against the wall trying to figure it all out. My equipment is as follows:
The story first starts out when I only had the components, 6x9's and the 4 channel amp. Everything worked just fine without any issues... Untill the day I decided I wanted my subwoofer back. I ordered up the 2nd amplifier and installed it as soon as I received it. Now, the 4 channel amp has an 8 awg wire running down the driver side door sill all the way back. The ground is going to the seat bolt on the respective side for the amp. The new amplifier I decided to get some 4 awg wire and run it down the passenger side as there wasn't enough room on the driver's. I grounded the mono amp to it's respective passenger side seat bolt. Right about now is when the ish hit the fan. I started the car up after completing the installation only to find the alternator whine of doom screaming out of all 4 speakers. I proceeded to remove the new amp to see if it was just the new amp that was throwing things out of whack. Even with the new amp removed and all new wiring unhooked, there was no change. The nosie was present with everything hooked up the way it used to be. All of my pre-out cables are crossing any power wires at a perfect 90 if at all. I proceeded to hook a single speaker directly to my head unit via the existing speaker wire and the noise was close to gone, but still there. In essense, it was much quieter only coming from the head unit in comparison to being amplified via the PG Amp. I proceeded to hook the entire system, power and ground to my father's battery to see if it was something within my internal charging system (alternator/battery) and the noise went away.
Now, my situation is this. Many people have told me that I should get a ground loop isolator or replace the ground wiring on my alternator/battery/chassis. I am hoping that this will simply be a last resort and that there is a root cause somewhere deeper. My reason for saying so, is that the system worked fine with the single amplifier, and then did not work anymore after the installation of the 2nd amplifier even when it was unhooked. My mind leads me to believe that something must have blown, not just gone bad over time. I went to Murray's to have my charging system tested and it was charging around 13.7 volts. He said it also stated that I had a normal charging pulse. I was thinking that it would have been possible to blow one of the diodes in the alternator to create this awful noise, but if the pulse is fine, then that's not the case. I'm very close to just ripping my alternator out to have a look.
Does anyone have any certainty into a given fix for this problem? Or am I going to end up tearing my car apart trying to fix this bastard of a noise! Any help is much appriciated.
