I have thought if the buzzing changes with engine speed it is an engine component not ground loop. Possibly alternator or ignition. for ignition check the coil ground and capacitor connected to the outside of it. for alternator noise I think you put a power wire filter on the amp and car stereo. Is the amp in the trunk?
It's not, stop guessing.
I'm not a car audio guy so that's why I'm looking for help. I guess I'm just going off of things I've read from other people. They seeme to have similar problems and thats what solved them.
Yes the amp is in the trunk. It's mounted right behind the seat and grounded underneath the seat where they "swivel". I know ground loop isolators can be had pretty cheap so I might just try it. Otherwise, I might just pull all of it and sell it
I just wanted to see what everyone thought before I did that
GLI's are just bandaids for the real problem. The problem is that there is difference in ground potential between the source unit and the amplifying unit. Basically you have a bad ground. Either that or the idiot that installed it ran the power and RCA"s on the same side of the vehicle which can pickup the noise as well.
I hate alt whine b/c it's a PITA to troubleshoot, and even worse when your not there to view it.
1. Check amp ground, if it is rusting or anything to that effect you need to re ground the amp. Clean off paint, screw to chasis. AND DONT use long ass screws, last thing you need is a hole in your gas tank.
2. Check connections behind radio, was a harness used? did they twist and tape?
3. Run a test ground, grab some 16-18awg wire and connect it from the ground of the radio, to the ground of the amp. This should even out the ground potential, or at least lessen the alt whine. This can be done without hiding it all, just run it over the seats and touch the ground of the amp. If it works, then you can worry about possibly running it hidden.
4. Disconnect the RCA's from behind the radio, is alt whine still present?
5. Is the radio a Pioneer? (these sometimes have grounding issues internally with the RCA's)
6. Old car batteries do not help your situation. An older car battery will have a harder time filtering out the leftover A/C ripple that the alt's rectifiers didn't get. Typical batteries are recommended to be replaced about every 3 years.
This is how we get rid of alt whine:
Identify
Isolate
Eliminate
