Horrible noise, whine in system..Part II

[Blood1]

Okay. I think I figured out what was causing this noise/humm/alternator whine that was ocuring in my car.

I pulled out the HU (KDC-X792) and was just staring at the dam thing since this has been going on for a few weeks now.

When I pulled it out as far as I could the noise went away, somewhat. As I got closer to the residing place where the HU goes it got louder again.

The installer guy from 6th Ave told me there is no way to get rid of this noise since it's caused by electronics that reside right next to where the HU goes. I didn't want to believe him at 1st but I don't see a way to get rid of it.

So today I pulled out the HU, and threw the Ground Noise Filters back on the incomming RCA's and the noise was almost 90% gone when the GNF were not near the inner housing where the HU resides. Then when I started to move them back in that hissing, and when I hit the gas the alternator noise came back. Both were not there when it was out of the HU-home.

Can someone tell me HOW do you get around, fix this?

What I ended up doing, which didn't fully correct the issue: was just placing aluminum foil on the inside bottom of where the HU goes. Next I wrapped the GNF plastic housing-body in aluminum foil and then stuck that into a static free Hard drive bag. It kinda minimized the ambient EMF from the other electronic components but I can hear the hummm and the alt.whine still.

I did absolutely everything under the sun for checking wires, grounds, RCA's, running the lines on opposite sides of the car, etc.... (Check original thread topic)This is the only thing I cannot determine how to fix or address.

In that spot where the HU goes, yes there are the cars electronic components, air bag computer, etc that just give off EMF and the HU is sensitive to this. Is it just the HU. I mean why didn't the stock HU have this issue?

Does anyone have a better idea or solution? Tomorrow (7/10) I'm going back to 6th ave and just going to tell them, uh fix this somehow but I don't see how they can. :

[rjdmmfl1]

Okay. I think I figured out what was causing this noise/humm/alternator whine that was ocuring in my car.

I pulled out the HU (KDC-X792) and was just staring at the dam thing since this has been going on for a few weeks now.

When I pulled it out as far as I could the noise went away, somewhat. As I got closer to the residing place where the HU goes it got louder again.

The installer guy from 6th Ave told me there is no way to get rid of this noise since it's caused by electronics that reside right next to where the HU goes. I didn't want to believe him at 1st but I don't see a way to get rid of it.

So today I pulled out the HU, and threw the Ground Noise Filters back on the incomming RCA's and the noise was almost 90% gone when the GNF were not near the inner housing where the HU resides. Then when I started to move them back in that hissing, and when I hit the gas the alternator noise came back. Both were not there when it was out of the HU-home.

Can someone tell me HOW do you get around, fix this?

What I ended up doing, which didn't fully correct the issue: was just placing aluminum foil on the inside bottom of where the HU goes. Next I wrapped the GNF plastic housing-body in aluminum foil and then stuck that into a static free Hard drive bag. It kinda minimized the ambient EMF from the other electronic components but I can hear the hummm and the alt.whine still.

I did absolutely everything under the sun for checking wires, grounds, RCA's, running the lines on opposite sides of the car, etc.... (<FONT SIZE=""1""><FONT COLOR=""Blue"">Check original thread topic</FONT></FONT>)This is the only thing I cannot determine how to fix or address.

In that spot where the HU goes, yes there are the cars electronic components, air bag computer, etc that just give off EMF and the HU is sensitive to this. Is it just the HU. I mean why didn't the stock HU have this issue?

Does anyone have a better idea or solution? Tomorrow (7/10) I'm going back to 6th ave and just going to tell them, uh fix this somehow but I don't see how they can. :

its the head unit my man... after reading this, I'm 100% positive... honestly, I would bet money that if you go and purchase another headunit from another company other than Kenwood, it would sound different... as I mentioned, its not the first time I've heard of kenwood headunits not having enough shielding and picking up horrible engine whine... even amongst their top units.... you may have to just get another headunit... perhaps an alpine headunit!

[Blood1]

Doc, man I wish you were right and it was that easy, but no.

Today I spent another several hours with Al the installer guy at 6th Ave. Again we tried a bunch of different things and nothing helped. We re-tried, running highest grade RCAs, running a ground wire from w/in the RCA to a ground no good, he tested the resistence, etc...

We did even hook up another head unit, a Pioneer 710BT model and the same exact noise was there.

To sum it up, what finally shed light on the source of the problem was, he hooked up an external 12V+ power supply to my head unit and we turned on the car. The noise was gone.

The noise is originating from w/ my cars power supply-lines somehow.

Al used to work at a Nissan dealership and he's sending me to one and they are going to replace my spark-plug-coils. Since my car is still way under warranty.

I'll be getting that done sometime later on in the week.

If that doesn't help then I'm torching the car.

[rjdmmfl1]

Doc, man I wish you were right and it was that easy, but no.

Today I spent another several hours with Al the installer guy at 6th Ave. Again we tried a bunch of different things and nothing helped. We re-tried, running highest grade RCAs, running a ground wire from w/in the RCA to a ground no good, he tested the resistence, etc...

We did even hook up another head unit, a Pioneer 710BT model and the same exact noise was there.

To sum it up, what finally shed light on the source of the problem was, he hooked up an external 12V+ power supply to my head unit and we turned on the car. The noise was gone.

The noise is originating from w/ my cars power supply-lines somehow.

Al used to work at a Nissan dealership and he's sending me to one and they are going to replace my spark-plug-coils. Since my car is still way under warranty.

I'll be getting that done sometime later on in the week.

If that doesn't help then I'm torching the car.

dam* my man, looks like you have a bum deal.. from your previous description, I was sure it was the headunit... honestly, if that' s the problem, one way to fix it would be to run another power wire from the battery, and place a relay inline and hook the relay up to an ACC source from the fuse box. sounds roundabout, but that may do it.

Honestly, I've never heard of an engine whine situation this bad before! sounds annoying bruh... wish I could be of more help, but I'm at a loss

[Blood1]

one way to fix it would be to run another power wire from the battery, and place a relay inline and hook the relay up to an ACC source from the fuse box. sounds roundabout, but that may do it.

So, just to clarify, run a new power line, Like I did for the direct ground off the (-) terminal of battery, off the (+), put an inline fuse relay along the way and then hook that up to the HU's yellow line?

I don't quit follow this part: "hook up the relay up to an ACC source from the fuse box. "

When I run a new power wire directly to the HU do what?Battery-->[New_10AWG_Powerline]--------->HU?

or

Battery-->[New_10AWG_Powerline]----[In_line_##A_Fuse]----->HU?

If this way, where do you get in_line fuses for this purpose? Car shop? and what rating #? 20A?

Thanks!!!

[Blood1]

And my fu-king nightmare continues on.

Today I purchased the in-line fuse, some 10A fuses and stopped by my parents for help. I go there b/c where I live, I can't work on my car in the street.

I ran the 12Awg line from 12V (+) terminal on battery to my HU. I was really, really like, this is going to work, no more noise, no more f-in noise, clear signal..

So I removed the RCA Ground loop noise filters, and the power loop noise filter. Hooked up all the wiring back up and last thing I do is put the 10A fuse into the inline fuse thing I got. Of course the sh1t 4 brains a$$holes at pepboys sold me the wrong size fuses for the in-line fuse they sold me. So i had to pull one out of my car. The inline one I got required the very small fuses, not the normal size ones.

Anyway found one, pop that in, roll up the windows turn it on and with the volume at 0 i hear sssssssszzzzzzzzzzz. Hit the gas and my alternator music comes over the speakers....

DIE U FUKING CAR!!!!

My dad who is helping me is just like, "why don't you just return all this nonsense." Good thing he's my dad or I would of ripped his heart out like in Indiana Jones: Temple of doom.

So at this point, I have totally exhausted every possible option and it's down to pure electrical mechanical noise interference coming over the power line into my HU.

I made an appointment with the guys at Nissan. I'm hoping he is going to test the alternator and change the spark-coil/plugs.

I doubt that will fix it. I'll just be taking a vacation day to get that done and spend it in the lobby of a service center with other angry people.

If that doesn't do anything then I'm just going to have to use the RCA & Power loop filters and live with it.

[Blood1]

I really really got very angry today. If your following this post, I went to the Nissan dealership this morning and man what f-in nerve. Basically this was my last hope in resolving the noise but it was a real waste of time. I was going there to have them check the spark coils and alternator for a possible reason for the noise coming over the power lines.I arrive and I sign the 1st hour is $98 for diagnostic fee. I'm thinking to myself uh is this really worth it? He says well if it is your alternator or spark-coils then it's covered by your warranty. (only have 30K on the car and have extended to 75K) So I sign it hesitantly. I'm waiting in the waiting room looking at my car still parked for 30min, the whole time going is it worth $98. Um.. While thinking I see someone take it for a ride. They go in the back and I wanted to just to talk to the mechanic to explain all the sh1t I'm going through with this car. But he's not there. I'm looking around and and I'm like wtf is he.. The meal truck pulled up so they are eating. So fine, I'm start to look around the shop and I see a f-in GTR (aka Godzilla) I ask if I can go look at it and 1 mechanic is like go ask the boss. I don't bother.

So I go back in the waiting room and 5 min later go back to see if mechanic is working on my car. I see he is but as I'm about to go into the shop the bald headed fat a**(o) shop manager is like 'sir you can't go back there, what if something happens to you.'"I would like to just go speak to the mechanic to explain the problem and what I've done so far." "no sir.. If you have a question you can see the advisor."

I can tell this a$$(0) isn't budgging so I go look for the advisor. Of course he's not at his desk so I go looking for him. I then look through the shop glass and see him next to my car with 1 mechanic and some other mechanic just pointing and laughing at my car. Laughing at my Big-3 cables. They close the hood and he walks back in and is like, there's nothing wrong with the car, alternator is fine and coils are fine.I just look at him and in my head go, HTF did you test everything in 2 minutes when you didn't even take the engine block protective thing off? Then he's like, "You have allot of after market stuff on that car there" very snugly/sarcastically. So I ask him what were you guys laughing at and he's like "Oh some joke that other mechanic brought up.."Bull F-in SH1t."So there's nothing wrong with my car.. Do you hear the noise..""Yeah yeah we hear it. You need to bring it back to where you got it installed. It's maybe a grounding issue or something.."

At this point I'm ready to scream

So I'm waiting and he hands me my keys and I didn't have to pay the $98 fee. So I left pretty pissed.

While driving back I'm thinking I have to take it to someplace where they would know wtf the big-3 is and maybe appreciate it and not laugh at the car. Yes an audio shop but then most shops are not going to help unless for a fee.

So I drove to my parents and just worked on my big-3 tweaking it by scrapping the paint off more, attaching another cable from alternator (-) to chassis. NOTHING. Same horrible noise.

I even tried out a new power noise filter that I was hoping would alleviate the issue. Not at all! Not a single bit.

So I spent several hours in 89 degree sun just going over every wire, every ground and nothing. I did hear a difference when going with the power cord I ran straight from battery, instead of 12V factory harness but I'm talking so slight that you couldn't tell unless you've been hearing this for days buzzing in your ears. (Oh yeah that's me..)

So in the end, I'm just going with the power filter and the RCA ground loop attached. Those pretty much clear things up but I still do hear a little bit.

I just cannot believe that out of the 100's of you on this site, yes a few of you have alternator noise but from the sounds of it, 95% don't have it. I'm just in disbelieve and it' can't be possible. How can you not have this problem and yet it just plagues me and a few others.

At this point I'm just going to go with it and use the filters. I've literally spent (6hrs, 6hrs back at shop twice, 4hrs, 4hrs) @ 28hours in the car just trying to get rid of this but it isn't going away.

For those of you who do have it, what year is your Altima? Mines an 07 so 1st year the new model came out. I'm just hypothesizing it maybe an issue with the 07's and not one in the 08+?

Anyway that's it. I got my HiFonics 1210D delivered today so tomorrow going to get it installed. I hope no magical surprises come out of that now. I'm thinking the dimming of the light will start to happen. just guessing here...

[LittleMan]

Do u have it hooked up at an amp? if u do that might be it. i had a problem with my punch amp in my 08 AC. I know it was my amp cuz when i switched it out it stopped. I had it repaired for about $100 bucks, i forgot the name of the part but i think it was the resistor that they swapped out. $100 bucks was worth the repair considering it was a 800.4

[Blood1]

What I'm thinking it could be might be the cheap amp kit i went with. I bought a BOSS 4Gauge amp kit and the power wire since I didn't have anything to compare it to, seemed ok.But once I installed the 2nd amp and my install guy used Tsunami 8-Gauge wire from the d-block to both the amps when I looked at the two and compared my quote on quote '4 gauge' line, it was the same if not smaller than the 8 AWG he used. So I'm thinking of taking that crap out and running a new either 0,1 or 2 AWG power line to the back and hopefully that could make a difference. I also seem to be very lacking in terms of boom. I also upgraded to the 12" VS12L72 kicker box and don't notice a difference from the 10" L7. I'm really hoping it's the power wire that is the cause of all this. Otherwise I'm just not truly satisfied with my overall setup.

[bthsburgess]

With my 2008 Nissan Altima 2.5 S, I had serious whining noise. Really, really bad. We went up to Monster cables, we replaced wires, we replaced distroblocks, we stuck in ground loops, replaced amps (twice)... everything.

The only solution that finally fixed the issue was a 40 farad cap and a Lineage Motorsports grounding system.

If you wanna hear about the kind of problems we had with mine, feel free to call Overdrive Audio and talk to Mike, 904-636-7845. You can also order a Lineage grounding kit from him.

The issue is more likely that your alternator isn't running at a high enough voltage level and the amps are struggling. With a cap, you get clear voltage and the power is "filtered" in a sense.

You need to ground your engine out thoroughly, with 4 gauge or higher cables from chasis to battery to cylinder block to alternator to chasis.

I'll post some pictures up after I go to lunch with how we did mine.

[Blood1]

Cool thanks Bthsburgess. I'd like to see how you guys grounded your engine. I did the big 2 1/2 upgrade. For the engine block I didn't know where to hook up the last 0 gauge cable i had. Plz post pics or send them to my email if you can. TIA!!

[bthsburgess]

Here's HOW it's grounded:



Note, the only difference from this diagram, is that we put a cable from the intake manifold to the alternator, then hooked one from the alternator to the chassis. (as opposed to intake -> chasis & alternator)

Here's WHAT it looks like:



Btw, I might want to add, another thing you may want to try to do is run a larger gauge cable from your distro to your sub amp, and a larger gauge cable from your sub amp to ground, this will help deliver more boom and also dump any excessive energy out. (see below, thick red from cap to sub amp, thick brown to ground).



You'll have to excuse the woodshavings, we're still a work in progress here.

While I think the ground is a big part, I think the cap plays a much bigger role in things. With a 120amp alternator like you and I have, you don't have much room to play. Getting a big 'ol cap installed acts like having a second battery in your car and provides more juice, not to mention allows for much better bass response. A 5 farad, 1 farad etc. cap is just not cut out for what most of us want. I went with a 40 farad, spent about 300 bucks on it, but my bass rivals people that are using 1000+ watt amps and my sub amp is only a 400-2.

Hope this helps you, because trust me, Overdrive told me on multiple occasions that my car was possessed with demons. Turns out I just needed a little power boost and a sufficient energy ground in the engine.
Modified by bthsburgess at 2:07 PM 8/27/2009