Alternator Whine after amp/deck install - 986 Forum - The Community for Porsche Boxster & Cayman Owners

chitowndad · 05-18-2008, 04:28 PM

I forgot to mention that I also tried grounding to the brown wire behind the drivers front headlight and I also still had the whining sound. That brown wire is the ground from the head unit. It wasn't until I found a fresh ground source did my whining sound go away. Now I just need to figure out why I'm getting a pop sound when I turn off the car!

Daryl80 · 05-20-2008, 12:09 AM

Hi chitowndad

I too faced that dreaded alternator whine. Ended up pulling everything apart, as I just had no idea where the fault could have been

Never occurred to me, that it was the FACTORY ground!!! Aaargh,

Anyway, can you please advise on where did you hook your new ground wire?

More so, do you have an amp?? I'm trying to install one in the front boot, but am not seeing anyway around avoiding the battery.

Thoughts?

Thanks

Daryl

rick3000 · 05-20-2008, 04:19 AM

That is weird because normally, the whine gets worse at louder volumes, also the whine increasing with RPM is normal (mine did that). I would recommend a few things, that may help: ground everything to the same ground point, buy a high quality ground loop isolator, and/or like insite said, get higher quality cables.

chitowndad · 05-20-2008, 06:56 PM

For the Avic D3 mute and parking brake bypass I simply grounded to the bracket for the old amp. Worked for several days but oddly, my whine came back today, so I'll need to find another source! Grrr.

I'll mess more with this over the weekend.

-Steve

chitowndad · 05-21-2008, 05:47 PM

Ok, so I bought a ground loop isolator from Radio Shack (hate that store) and my humming is gone. I recommend this solution.

-Steve

boxs2000 · 05-21-2008, 10:23 PM

Alternator whine can also be reduced by adjusting the line level input on the amp. Sometimes when the amp is turned up too high it creates this. Check ground sources, preferably only ground the audio units to one round and dont share it with sources like the headlights as those are known to cause a noise. Also you did not mention what kind of soundstream amp, I had an older (10y/o) one that I had in a prior vehicle that sounded great and worked flawless (no noise etc) but when I installed it in my Boxster I got a alot of engine noise. Took it out and installed brand new Alpine amps and no noise or issues. Just new technology is my guess. As far as antenna wire adaptors, use any german style ones will work.