2008 Avalanche with Engine whine. Yes I read stickey, yes I searched, going crazy

[IgnoreMe 5,000+ posts]

pioneers are pieces of shit. im with deuce. after buying one for my girlfriend and having it skip constantly while parked on brand new cd's, ive realized, they **** dick. huge dick.

 

[duece212 5,000+ posts]

Maybe try running a ground to the frame of the truck instead of the floorboard. I know it reads decent on the dmm, but when you have power flowing through it, maybe its still a bottleneck. Just an idea

 

[badstang123 10+ year member]

Disconnect all the rca cables at both ends. Next you need to take the cables one at a time and see if one of them is dead shorting either center conductor to exterior shield or to chassis ground. Verify this and post the results. If you find one cable that is dead shorting, it is more than likely the culprit. Those old Crossfire amps were highly reliable, I never once had a issue with noise from them in a vehicle.

This sounds like a good next step. Especially since the problem is intermittent. Could be something moving just a touch. I'll give it a shot tomorrow.

 

[badstang123 10+ year member]

Great news. It's fixed itself overnight by sitting //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

Anyways, I went out and started by disconnecting the subwoofer RCA's at both ends. Started the car and had the original (Normal since original install) minimal whine. So problem fixed right!!!! Well maybe not. I then reconnected them and the noise didn't come back. I really wish I had started the truck first before disconnecting anything to see if it sitting alone made the whine stop (Mind you the problem is intermittent and this has happened before). But I've just left the dash out the past few days so it was easy and quick just to start disconnecting stuff.

Disconnecting at both ends starting the car and then turning off and reconnecting the RCA's wouldn't make any difference would it? That couldn't have made the difference right?

For now I'm going to leave it apart and every couple hours wait for the whine to come back. The last thing I want is to put the dash back together again and have to pull it out. Although I'm getting really good at it //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[badstang123 10+ year member]

Alright I have finally pinpointed the culprit. What I am still unsure of is what I need to do to fix it. When I get the loud whining with a static noise through the speakers and I unplug the FM antenna the noise gets worse. I plug it back in and it gets a little better but is still bad. So the noise definitely seems to be related with the antenna somewhere.

What do I check? What do I consider changing. I mean the truck only has a few thousand miles on it so it's almost brand new. And the only added component between the head unit and the stock antenna piece is a short adapter. Could the adapter be bad? Is there something else back further towards the stock antenna that would cause it? What gets me is it's worse when unplugged then when plugged in. Let me know what you guys think. Thanks

- Justin -

 

[forbidden 10+ year member]

Where have you grounded the head unit to again? Try ungrounding it from wherever it is and running a temporary ground wire to one of the amplifiers.

 

[NeverEnuffBass 10+ year member]

Where have you grounded the head unit to again? Try ungrounding it from wherever it is and running a temporary ground wire to one of the amplifiers.

x2 I've had good luck in similar situations with grounding the head unit and amp in the same spot

 

[Supergumby5000 5,000+ posts]

I have the alternator whine as well with my unit.

When i get some time, im going to ground the HU to the front battery and ground the RCA's on the back of the HU, and i'll report back //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[badstang123 10+ year member]

Where have you grounded the head unit to again? Try ungrounding it from wherever it is and running a temporary ground wire to one of the amplifiers.

I'll try grounding to the amps and see if it makes a difference. Currently it's grounded through stock harness and scosche onstar module. But I've already tried an additional ground to the chassis for the head unit and it didn't help (2 different ones actually) And I tried grounding the RCA's to the headunit chassis with no difference. I'll try directly to the amps though.

You guys don't think anything with my last post and the FM antenna has anything to do with it?

 

[NeverEnuffBass 10+ year member]

I have the alternator whine as well with my unit.
When i get some time, im going to ground the HU to the front battery and ground the RCA's on the back of the HU, and i'll report back //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

I'll try grounding to the amps and see if it makes a difference. Currently it's grounded through stock harness and scosche onstar module. But I've already tried an additional ground to the chassis for the head unit and it didn't help (2 different ones actually) And I tried grounding the RCA's to the headunit chassis with no difference. I'll try directly to the amps though.
You guys don't think anything with my last post and the FM antenna has anything to do with it?

Noise in GM trucks seems to be a common problem whenever one comes in the bay for noise first thing I do is reground the radio if it has been connected to the factory radio ground. Most of the time but not always it solves the problem

 

[badstang123 10+ year member]

Noise in GM trucks seems to be a common problem whenever one comes in the bay for noise first thing I do is reground the radio if it has been connected to the factory radio ground. Most of the time but not always it solves the problem

I tried two seperate grounding spots in addition to the factory harness and neither made a difference.

Edit: Do you get rid of the factory harness ground? Or just do an additional like I did?

 

[loopkiller 10+ year member]

The whole antenna noise thing makes me think that you were simply grounding through the antenna wire. I know that you say you have a good ground and have tried different grounds, but I still think that it is a grounding issue at the HU.

If you unplug all of the RCA cables from your HU, do you still get the noise?

 

[badstang123 10+ year member]

I didn't run a ground directly to the amp grounding location yet but I did disconnect each of the RCA's individually. The only time I got no whine was when both front and rear RCA's were disconnected. With just front or just rear disconnected I still got excessive whine and when I disconnected the subwoofer RCA's it made no difference to the speakers.

On another weird note I ran into some weird conditions before even trying to disconnect the RCA's that might mean something but I haven't figured it out yet:

When I first went to my truck this morning and started it up with the antenna disconnected and no engine whine. Then I turned the truck off, plugged the antenna in and still had no whine. I put things back together and still no whine.

Then, however, when I reached anywhere from 32-35 volume (of 62 total) or about 50% volume I started getting static or crackling from the front passenger side and the driver side speakers volume goes down very low. What would cause this? Head unit? Amps? Speaker connections? If I took the volume back down to 30 or below it went back to normal...no noise and all channels worked properly.

Let me also say that I noticed initially when I went from no whine to a lot of whine that it happened after first starting the car (For no apparent reason) or after I played the music at high volumes, I would get that shorting of sorts, turn the volume down and the whine would be there.

Well after all that above I then left the truck to sit and for me to cool off and then when I restarted later the whine was back and I disconnected the RCA's one at a time like I stated in the first paragraph

Thank you all for the help so far. Typically I can figure things out on my own or by searching a little. This is just a very odd problem but I have a feeling these two separate symptoms are one problem that brings about both of them. I'll report more when I have run a separate ground to the amps grounding location.

- Justin -

 

[duece212 5,000+ posts]

Have you tried running a ground to the frame for your amps yet instead of the floorboard, maybe your door speaker amp was getting pissed when you cranked it up and thats why the volume dropped and distorted, your amp was having problems flowing power out the ground

 

[badstang123 10+ year member]

Have you tried running a ground to the frame for your amps yet instead of the floorboard, maybe your door speaker amp was getting pissed when you cranked it up and thats why the volume dropped and distorted, your amp was having problems flowing power out the ground

I'm considering a straight run to the battery actually. But that amp isn't pulling anything compared to the sub amp which has no problems. And it's not like a sheet metal floorboard... this is a piece of maybe 1/4 thick metal plate. And I checked voltage at the amp when turning it up and it was over 14 volts when it was happening. But I am still considering a better ground like you mentioned. Tomorrow I will do the head unit to amp ground and maybe relocate the amp ground too. The weird thing is the system was fine for about a month at all volume levels. That's what has me so confused. But new grounds are on the agenda for tomorrow.