I've got some poltergiesty **** going on here. Working on getting rid of my alternator whine and I undid the ground on the headunit and the head unit stayed turned on. That shouldn't happen. I unplugged the antenna (don't ask why I don't know) and the system started popping real loud and making some crazy noises. So I quickly reconnected the ground and it went away. WTF is going on here.

Yes it is a Pioneer and I have read about grounding the RCA's but that didn't seem to work. I'm almost positive the deck is bad and it's grounding itself through some wire some where. I've gone through the entire harness and there are no bare wires touching anything anywhere. I did end up realizing I ran the passenger speaker wire right on top of the amp power wires so I moved that but that didn't solve it.

I really don't want to put a ground loop isolator in as I know it's something simple but I'm kinda at my wits end here. Wife wasn't real happy when I mentioned buying a new head unit but that might be my only option.

Here is how it is set up currently.

Head unit wiring harness grounded to battery
Head unit chassis grounded to car chassis
Amps grounded to bolt in trunk

 

the deck will still work because it can remain grounded through chassis ground or it will ground itself out though the audio outputs also, but sound will not be as good. If you are getting whine and you are running a 4 channel amp, it is most likely the ground in your trunk is bad. the tack welds holding the car together are not the greatest ground, so you probably chose a bad ground point. could also be crappy non-shielded RCA's if you didn't use good quality wiring.

 

did you scrape the paint around the bolt, or just take it out and throw grounds on there and put it back in?

 

Only a 2ch amp. RCA's are T-Spec V10's. I've checked and moved amp grounds several times with no change. Also grounded the headunit chassis and run the ground from the headunit to the battery. I've never seen a radio work with the ground wire being removed or seen this crazy loud popping from the antenna cable being removed.

Paint scraped around bolts. This is the single most irritating problem I've ever argued with in my entire automotive hobby career.

 

If you get popping my removing the antenna wire you probably need ground loop isolators on the RCA's. theyre cheap and should fix your problem. I have a small battery cell in the trunk for my audio, so I have dedicated 1/0 power and ground wire runs giving me direct battery ground. that helped sound quality a lot for me. Grounding amps direct to the battery made a big difference. The panels you probably are grounding on are usually not connected very well to the car frame. only by tiny tack welds and glue which make frame grounds on these cars difficult. I have a G35 coupe but its basically the same.

 

Those seem like a band aid. Maybe they are necessary in some cases? I think I'm going to up the amp wires. Go to 0ga from battery to distribution block, then 4ga to the amps and then 4ga back to the battery for ground. Currently I've got 4ga for the sub and 8ga for the speakers. And redo all of the wiring just to make sure nothing weird is happening.

 

Upping the wire size won't help you. I only run that wire size because I have my air setup back there as well as 1600 watts running off of those wires. The best things that could help you are ground direct from front to the trunk(you can use 4ga), and the ground loop isolators on rca's. It is a 'band aid' for a deck with a grounding problem. or either your deck or amp have a circuit problem somewhere.

 

You're right it won't but since I'm changing stuff up it won't hurt. And I talked to a guy at the office who has been doing car audio for 25yrs and the moment I said alternator noise and pioneer he said it's the radio. So I bought an Alpine today haha. Wasn't a fan of the pioneer anyways. Hopefully that and new wiring and I can put this to bed once and for all.

 

Well I got the alpine in and the problem is gone. After 7 weeks I'm finally getting to drive my car. Going to get the system tuned tomorrow. I can't wait.