Engine whine and ground loop fixes... take two

[CRAZYCORNUTS18 10+ year member]

ok my engine whines like crazy and its really anoyying i made sure that my amp was grounded good, i sanded it down and everything and it still whines what to do next?

 

[uPsDdOWN 10+ year member]

Ok, a few other extremes I have done in the past.... I totally isolated the HU from and ground or power source at the front of the car. HOW?

1)- Depending on how your HU is installed your gonna have to get creative and make sure no part of the HU or the sleeve touches ANY metal in the dash..this includes the rear support bracket... your on your own here.. there are a million differnet ways to do this.

2) - I ran new power wire (8GA--because I'm only using line outs, no amping required at the deck) from the dist block and common ground block in my trunk to the dash. At the dash I split the two power wires, One to the constant (yellow or orange lead depending on make) and one to simple Radio shack 12 volt, normally open relay. Power in, power out.... then use the factory wire from the fuse panel to trip the relay. DO NOT Ground the relay ground to the same place as the HU ground tho! You will defeat the whole purpose.

3)- It cannot be said enough... USE SHEILDED or Twisted pair RCA's for the run to the back and if your head unit doesn't do it, get a line amp and jack up the power to at LEAST 4V before running it to the trunk. Amps, crossover, whatever. the higher the output the less likely you will inherit nose from other sources like computers, harnesses, etc in the car.

4)- It should seem obvious, but if it is alternator whine you are dealing with you Should go right to the source. You may consider replacing the Alternator diode bank (that little circuit board on the back where the removabele panel is.. depending on what kind of alternator you use of course, and also replace and reground the regulator--usually located on the firewall or in newer cars under on of the many plastic boxes under the hood.

DO THE BIG THREE... Ground ground ground... make sure other primary electrical components are properly grounded as well... accessories, aux lites, if the sound only happens when you use the brakes (pops and clicks) then check all the relays in the braking system, when your lights are on? When you roll up/down electric windows...

This kind of troubleshooting is all about isolating the bad ground and replacing it. The reason you get the whine/noise is because something is improperly connected or loose and that "source" is "borrowing" (if you will) from your sound system,....the most obvious way that you Hear it before it appears somewhere else.

There is obviously a LOT more to this... it is just gonna take some work and patience. Start isolating stuff..

 

[spike_e 10+ year member]

i just got a pioneer deh-6800mp and i did the wire around the rcas and it worked!!!!!! i had horrible whine and now i have none!!!!!

 

[synikalt 10+ year member]

I Wrapped it! worked well for me in the end! at first i was still gettin bad engine noise...but idk what i did,i kept checkin wit different rcas...and i had to finally switch my rcas around..cause i have 2-channel split to 2 y-adaptser so i can plug 4 channels into my 4-channel amp...no engine noise now...maybe but barley minimal...u have to really listen cause the sound at idle is louder than engine noise

THIS FIXED IT!

THANX!

 

[rmdl51 10+ year member]

So I'm confused, Will grounding RCA's to HU chassis will blow the fuse or not? I have a Pionner DEH-7700MP with a terrible noise and I don't know how to fix it, even I install ground loop isolators the noise didn't went away. Anybody can tell me for sure if I can try this safe?

 

[jmanpc 5,000+ posts]

yes, its safe. lots of people have done it.

 

[413audio 10+ year member]

do you guys think this would solve a staticy like noise coming from my non amplified speakers only when the subs are on? yes i have a pioneer HU.

 

[79corona 10+ year member]

I just installed a new system. The car was prewired for four speakers. I'm getting static through the speakers, even with an iPod attached. This usually gets worse when volume is increased. I believe my system is pretty well matched. Any ideas?

 

[ace_800 5,000+ posts]

Ok, heres one for you.

Nissan Murano with a HU that cannot be replaced so I have a pac unit(ROEM-NIS2, didn't have to cut or tap wires, plugged into stock HU) and I have had engine noise for the longest. I have check and moved my amp grounds to no availe. Should I use another ground for the hu or just go with the ground loops.

 

[79corona 10+ year member]

Why can't it be replaced?

 

[ace_800 5,000+ posts]

Its connected to the a/c controls and everything else on my center console(ie. oem 6.5 display, maintenance controls, etc.)Metra and Schose(sp) don't make and are not in the process of making a kit. Kind of like the Ford kiet that runs like 80 bucks but needs to be much more complicated. A big ass cpu board( or some ****, its about 9"x11") runs through the center console and by removing the oem cd changer/player the cpu board is still there, only the cd slot is all the way through.

pic of behind console

 

[jda 10+ year member]

After fighting alternator whine for some while, as well as the on/off thump, grounding my RCAs has fixed the problem with my 5900. There is not any alternator whine left. I am both angry that I had to do this with a known problem but also happy that the whine is gone.

 

[etznova 10+ year member]

well I've got a Premeir 780

i had it in my bonneville with no noise

i then got new truck i put the deck in and I got a horrible rumble through the sub when volume was at zero and in the background of the music

i tried every other noise remedy with no sucsess

I then grounded the RCA's and atlast no rumble

**** Pioneer's

 

[Ryley87]

There are alot of disappointed pioneer customers on here //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif and tomorrow i plan to install my system which has a pioneer deh-p6950ib HU...

So i had better do this right the first time.

So i have some shielded rca's with some small ground wires coming of the casing at each end, does this mean i don't have to worry about grounding the rca's at the back of the unit with bare wire as previously pictured several times?

secondly can i ground the HU to the firewall or something in that locality and ground the amp to the floor pan under the seat without introducing ground loops? It has been suggested to me that amp and HU grounds should be in the same area, would just like to see how many people can confirm/discredit this.

I plan to wire the rca's and turn on wire down one side of the car and the battery wire down the other as many people advocate this practice. Should i run speaker wire for the parcel shelf speakers down the same side as the rca's away from the power wire?

Cheers.

 

[jmanpc 5,000+ posts]

The wire built into your RCA cables is a remote wire, so that you don't have to run a separate wire.

You can ground your head unit to the firewall or what have you, and not have any ground loops, but the safest option is to ground to the same place as your amp(s) or to the negative post of the battery.

 

[SethPhillips 5,000+ posts]

i love pioneer's other then this.................

 

[Home2CarSpeaker]

I have a serious alternator whine problem along with the accompanying thuds during channel switching etc. I have a Pioneer DEH P-880 HU which has performed flawlessly with the amp and sub I use until the other day when I was turning up the power amp sensitivity a little and I got a loud screech. After going through all my speakers, testing the amp with another source etc. I isolated the HU as the culprit. It hasn't screeched again yet but I have the alternator hum quite prominently. Is there any chance something shorted in the HU in terms of grounding or fuses or could my alternator just be about fried. Any help would be appreciated.

System Pioneer: DEH-P880 Head Unit, Sirius/Pioneer Receiver, Jenson 780 Watt Stereo Power Amp, Kenwood Powered Bazooka Sub, B&W 5 1/4" Home Audio Speakers W/ 1" Dome Tweeters in Front, 3D Acoustic 6.5" Home Audio Speakers W/Road Master Tweeters in Back.

 

[Ryley87]

The wire built into your RCA cables is a remote wire, so that you don't have to run a separate wire.
You can ground your head unit to the firewall or what have you, and not have any ground loops, but the safest option is to ground to the same place as your amp(s) or to the negative post of the battery.

Are you sure about that the wires are black with ring terminals...

Can someone tell me how to post a pic so i can show you the rca's and anything else in the future.

Thanks for the reply,

Cheers.

 

[TurdFergueson2 5,000+ posts]

This was very useful. I have a Premier 690ub And all of a sudden i started getting the alternator whine. I have not had a chance to do the grounding rcas thing yet, but my local sound shop told me the same thing. they said to ground the rcas though. I will post the outcome after i try this tonight.

 

[TurdFergueson2 5,000+ posts]

I finally did it correctly and it worked!!! At first i had it half assed and i still heard a lot of noise. After redoing it, It almost cleaned it up completely. I will try some other suggestions (I have a set on the back of my HU that come out like a Y adapter, and I need to ground those) And i also will try grounding the HU from the factory spot to somewhere else.