Engine Noise :(

ConchZ2 · 09-26-2009, 10:17 AM

Engine noise in the vehicles stereo speakers. It’s a pretty common problem when an aftermarket radio or amplifier is installed. The most common description of the noise is a whining sound that gets louder as the engines RPMs increase. This is very annoying and sometimes embarrassing. If your new automotive stereo system is causing unwanted engine noise the fix can be relatively simple.
The normal cause of engine noise in the stereo system is the ground. In any 12 volt system there is a 12volt + and a 12volt -. Often times a vehicle manufacturer will ground all of the dash instruments to one central location. This is great for them but bad for car stereo enthusiasts. When we hook up our new stereo we often times (if done properly) will use an installation wire harness. This wire harness will match up to the vehicles wiring exactly. So your ground and power are coming from the fuse block and a central ground location (vehicle standard).
A simple solution can usually fix this engine noise problem. Change the stereos ground location. Most times this can be done and un-done (if it doesn’t help) very easily. Behind the stereo will be anywhere from 10 to maybe 16 wires coming out of the stereo into a wire harness clip. Between the stereo and the first wire harness clip you will need to cut the ground (Black 12V-) wire.
This will break the ground and the stereo will not turn on at this point. The part of the wire that is coming from the back of the stereo will need to be lengthened and run to an alternate grounding location. Most of the time there is a bare metal dash frame under the upholstery that you will see when the stereo is removed from the dash.
With a digital multi-meter in hand you may test for a good ground source. Make sure to set the meter to test for continuity. You can make sure that the meter is set correctly by touching the lead ends together, this should give a beep or chirp from the meter letting you know that there is continuity. Clip one of the meter leads to a known good ground (somewhere in the door jam usually works) and then you may begin looking inside the dash cavity for a ground location.
Once you have a beep or chirp from the meter you know you have found a ground location. We’ll only know that this is a good location or not once the ground is hooked up and we turn the stereo on. Until then, cross your fingers and hope for the best. Hooking up the stereos ground wire to the new ground location is up to you. Every situation is different so you may need a crimp end or some other modifications inside the dash cavity to get the ground wire hooked up.
Just changing the stereos ground location will often resolve the engine noise problem. When this doesn’t work we resort to a “Ground Loop Isolator” or “Inline Noise Suppressor”. There are a few different styles that are used for different applications.
There are noise suppressors that are used in the power line, in the RCA/audio cable lines and some with 3.5mm stereo cable input and output. You must determine which is right for your application.
Some stereos will only create this whining when there is an auxiliary audio input used. These will usually be something like an MP3 player. There are ground loop isolators for use with MP3 players.

bigaudiofanat · 09-26-2009, 02:42 PM

Ground loop isolators are a last resort as they can omit or fade out certain freq in the sound, including ones that music would usually come out at. Always check different power places and ground as well before using one of them.

ConchZ2 · 09-27-2009, 09:25 AM

Noise suppressors are the last resort, as I stated earlier, and it might be the only resolution for engine noise problems.

The Weapon · 09-30-2009, 03:32 AM

I exchanged my RE-Q and the new one is working fine. The engine was the unit and not my install. It sounds a lot better with the new RE-Q and had i received a working RE-Q this install would have been easy and quick.

Total Cost for the RE-Q 5 $175

As far as sound quality I have to say I'm very impressed with what the RE-Q does when it's not making a bunch of noise.

jrniehaus · 10-31-2009, 03:35 AM

I had a hu replaced with no ground loop problems. Then I installed an amp and replaced all the speakers as well. Now I have a ground loop, which is annoying. Does this same technique work for my situation, since I grounded the amp to the frame in the middle of the car? Just checking, or if I have to do something totally different to get rid of my new ground loop. Thanks in advance.

bigaudiofanat · 10-31-2009, 08:40 AM

Quote:

Originally Posted by jrniehaus

I had a hu replaced with no ground loop problems. Then I installed an amp and replaced all the speakers as well. Now I have a ground loop, which is annoying. Does this same technique work for my situation, since I grounded the amp to the frame in the middle of the car? Just checking, or if I have to do something totally different to get rid of my new ground loop. Thanks in advance.

How and where did you run your rcas and power wires? Did you sand the ground spot down to bare metal before putting the ground wire on? Were did you ground your head unit too? Also what kind of amp is it?

jrniehaus · 10-31-2009, 12:49 PM

the hu was installed using the factory harness connector. so i believe it was connected to the ground through that connector. I would have to double check that to be sure. I ran the power along the passenger side and speaker wires with rca along the driver side and the remote lead as well. Figured those would be ok due to low power, compared to the power wire. Jl 900 5 amp is grounded in the trunk to a bolt that I didn't sand because it was pretty large in size(thought it would suffice). I am just wondering if the hu wasn't grounded accept for the factory connector it is connected to. (I never installed the deck, just
added the rest)

bigaudiofanat · 10-31-2009, 03:49 PM

You have to have a clean metal surface so go to your ground and SAND the paint and all off. Also as far as I knwo and all the head units I have put in the z's there is not factory ground wire that is used in the aftermarket harnesses. So I would check on those if you did somehow use the factory ground unhook that wire and ground it to one of the 4 bolts were the shift knob is. But the most important thing is to sand that primer and paint off that ground spot.

jrniehaus · 10-31-2009, 04:48 PM

I looked at the pics on the web site that was linked to your response, and noticed you had a blue 370z you did an install on. In the back where the crossbar is (the one directly behind the seats) directly below that in the little cubby of the trunk there are two silver screws attached to a black tab that is screwed to the trunk. The one on the left is where I bolted down the ground. So, should I take the bolt off and sand off the paint from that, or can I move that tab so that I can sand the trunk below that and mount the ground between the black tab and the trunk itself? Or, is there a better place to put the ground?

bigaudiofanat · 10-31-2009, 08:12 PM

Sometimes it does not matter were you put your ground wire, yes you could put it were I put mine at. BUT you have to sand the spot.. Electric can not travel easily with paint and primer on top of the metal.

jrniehaus · 10-31-2009, 11:03 PM

I didn't see where your ground was. Plus I haven't tried yet, but I don't know if I can get that black tap off of the trunk area to sand under it. It may, but I haven't tried yet.

jrniehaus · 11-02-2009, 05:14 PM

Ok, so I actually moved the ground from the amp to a different bolt in the trunk and sanded it real good. Still have a engine buzz noise. Wondering if it is now the deck that needs to be grounded to the body somewhere also. I believe you grounded yours to a bolt near the gear selector? And my Hd 900-5 also seems to have a bit of a hissing noise when I set the input gains to the 24.6(fronts) and 44.7(sub) voltage levels. Maybe I should turn the amp gains down a bit to make the hiss less?

bigaudiofanat · 11-02-2009, 06:27 PM

Who makes your head unit? If it is pioneer you might have to ground the rca plugs if you already grounded the unit to a clean place. 80% of the problems with noise are grounds that is why I keep bringing them up.

And yes I say pioneer because they are known for this problem. Here is a thread that might help you out more.

"Grounding the RCA's on the head unit
Many have had problems with Pioneer head units because of a poor internal RCA ground. To remedy this, simply wrap wire around the RCA's and screw the wire down to the head unit's chassis like so:"

http://www.caraudio.com/forum/showthread.php?t=198477

bigaudiofanat · 11-02-2009, 06:31 PM

Also if you still can not get it. Please contact me threw aim or yahoo so we can talk about the problem further.

SlikNik · 11-02-2009, 06:38 PM

I have the same amp and just finished my install last week. No engine noise luckily.
I ran rca's down the middle, power wire down the drivers side. New speaker wire from amp(under that black foam piece) to crossovers under the seats, to door components. When your wires start to get closer together as they get closer to the amp make sure they don't run parallel next to each other. If they have to cross each other I have always heard to cross them at 90 degrees. I used that bolt to the left of the remote sensor thingy that was talked about in another thread to ground my amp. Used a wire brush in a drill to clean it down to metal.
The head unit is grounded to the wire harness on mine.

09-26-2009, 02:42 PM	#32 (permalink)
bigaudiofanat Car Audio Installer Join Date: Jun 2009 Location: Magnolia DE Posts: 8,342 Drives: 2012 Infiniti G37x Rep Power: 853	Ground loop isolators are a last resort as they can omit or fade out certain freq in the sound, including ones that music would usually come out at. Always check different power places and ground as well before using one of them. __________________ Need help with car audio or electronics? Let me know!! Need Help Let Me Know Direct email address reimermatt@gmail.com Owner of: Dynamic Mobile Audio Follow me below https://www.facebook.com/Dynamicmobileaudio/

09-30-2009, 03:32 AM	#34 (permalink)
The Weapon Enthusiast Member Join Date: Nov 2008 Location: Tucson, AZ Posts: 286 Drives: 370Z Tour/Sport Blk Rep Power: 3372	I exchanged my RE-Q and the new one is working fine. The engine was the unit and not my install. It sounds a lot better with the new RE-Q and had i received a working RE-Q this install would have been easy and quick. Total Cost for the RE-Q 5 $175 As far as sound quality I have to say I'm very impressed with what the RE-Q does when it's not making a bunch of noise. __________________ Boosted Performance Comp Turbo - Tuner- CJM Fuel Return- Modified Berk CBE- ZSpeed Stage 4 Clutch - Southbend Flywheel - Tuned by Seb ~650whp - HKS Coilovers - SPL - Focal Audio 4 way Active - Audiocontrol DSP - Work CR 2P Last edited by The Weapon; 09-30-2009 at 02:53 PM.

10-31-2009, 03:35 AM	#35 (permalink)
jrniehaus Base Member Join Date: Oct 2009 Location: Phx,AZ Posts: 45 Drives: 370z 6spd sport mdl Rep Power: 16	question about my ground loop issue I had a hu replaced with no ground loop problems. Then I installed an amp and replaced all the speakers as well. Now I have a ground loop, which is annoying. Does this same technique work for my situation, since I grounded the amp to the frame in the middle of the car? Just checking, or if I have to do something totally different to get rid of my new ground loop. Thanks in advance.

10-31-2009, 03:49 PM	#38 (permalink)
bigaudiofanat Car Audio Installer Join Date: Jun 2009 Location: Magnolia DE Posts: 8,342 Drives: 2012 Infiniti G37x Rep Power: 853	You have to have a clean metal surface so go to your ground and SAND the paint and all off. Also as far as I knwo and all the head units I have put in the z's there is not factory ground wire that is used in the aftermarket harnesses. So I would check on those if you did somehow use the factory ground unhook that wire and ground it to one of the 4 bolts were the shift knob is. But the most important thing is to sand that primer and paint off that ground spot. __________________ Need help with car audio or electronics? Let me know!! Need Help Let Me Know Direct email address reimermatt@gmail.com Owner of: Dynamic Mobile Audio Follow me below https://www.facebook.com/Dynamicmobileaudio/

10-31-2009, 08:12 PM	#40 (permalink)
bigaudiofanat Car Audio Installer Join Date: Jun 2009 Location: Magnolia DE Posts: 8,342 Drives: 2012 Infiniti G37x Rep Power: 853	Sometimes it does not matter were you put your ground wire, yes you could put it were I put mine at. BUT you have to sand the spot.. Electric can not travel easily with paint and primer on top of the metal. __________________ Need help with car audio or electronics? Let me know!! Need Help Let Me Know Direct email address reimermatt@gmail.com Owner of: Dynamic Mobile Audio Follow me below https://www.facebook.com/Dynamicmobileaudio/

09-26-2009, 10:17 AM	#31 (permalink)
ConchZ2 Enthusiast Member Join Date: Feb 2009 Location: connecticut Posts: 329 Drives: 09 370Z red 6sp sprt Rep Power: 16	Engine noise in the vehicles stereo speakers. It’s a pretty common problem when an aftermarket radio or amplifier is installed. The most common description of the noise is a whining sound that gets louder as the engines RPMs increase. This is very annoying and sometimes embarrassing. If your new automotive stereo system is causing unwanted engine noise the fix can be relatively simple. The normal cause of engine noise in the stereo system is the ground. In any 12 volt system there is a 12volt + and a 12volt -. Often times a vehicle manufacturer will ground all of the dash instruments to one central location. This is great for them but bad for car stereo enthusiasts. When we hook up our new stereo we often times (if done properly) will use an installation wire harness. This wire harness will match up to the vehicles wiring exactly. So your ground and power are coming from the fuse block and a central ground location (vehicle standard). A simple solution can usually fix this engine noise problem. Change the stereos ground location. Most times this can be done and un-done (if it doesn’t help) very easily. Behind the stereo will be anywhere from 10 to maybe 16 wires coming out of the stereo into a wire harness clip. Between the stereo and the first wire harness clip you will need to cut the ground (Black 12V-) wire. This will break the ground and the stereo will not turn on at this point. The part of the wire that is coming from the back of the stereo will need to be lengthened and run to an alternate grounding location. Most of the time there is a bare metal dash frame under the upholstery that you will see when the stereo is removed from the dash. With a digital multi-meter in hand you may test for a good ground source. Make sure to set the meter to test for continuity. You can make sure that the meter is set correctly by touching the lead ends together, this should give a beep or chirp from the meter letting you know that there is continuity. Clip one of the meter leads to a known good ground (somewhere in the door jam usually works) and then you may begin looking inside the dash cavity for a ground location. Once you have a beep or chirp from the meter you know you have found a ground location. We’ll only know that this is a good location or not once the ground is hooked up and we turn the stereo on. Until then, cross your fingers and hope for the best. Hooking up the stereos ground wire to the new ground location is up to you. Every situation is different so you may need a crimp end or some other modifications inside the dash cavity to get the ground wire hooked up. Just changing the stereos ground location will often resolve the engine noise problem. When this doesn’t work we resort to a “Ground Loop Isolator” or “Inline Noise Suppressor”. There are a few different styles that are used for different applications. There are noise suppressors that are used in the power line, in the RCA/audio cable lines and some with 3.5mm stereo cable input and output. You must determine which is right for your application. Some stereos will only create this whining when there is an auxiliary audio input used. These will usually be something like an MP3 player. There are ground loop isolators for use with MP3 players.

09-27-2009, 09:25 AM	#33 (permalink)
ConchZ2 Enthusiast Member Join Date: Feb 2009 Location: connecticut Posts: 329 Drives: 09 370Z red 6sp sprt Rep Power: 16	Noise suppressors are the last resort, as I stated earlier, and it might be the only resolution for engine noise problems.

10-31-2009, 12:49 PM	#37 (permalink)
jrniehaus Base Member Join Date: Oct 2009 Location: Phx,AZ Posts: 45 Drives: 370z 6spd sport mdl Rep Power: 16	the hu was installed using the factory harness connector. so i believe it was connected to the ground through that connector. I would have to double check that to be sure. I ran the power along the passenger side and speaker wires with rca along the driver side and the remote lead as well. Figured those would be ok due to low power, compared to the power wire. Jl 900 5 amp is grounded in the trunk to a bolt that I didn't sand because it was pretty large in size(thought it would suffice). I am just wondering if the hu wasn't grounded accept for the factory connector it is connected to. (I never installed the deck, just added the rest)

10-31-2009, 04:48 PM	#39 (permalink)
jrniehaus Base Member Join Date: Oct 2009 Location: Phx,AZ Posts: 45 Drives: 370z 6spd sport mdl Rep Power: 16	I looked at the pics on the web site that was linked to your response, and noticed you had a blue 370z you did an install on. In the back where the crossbar is (the one directly behind the seats) directly below that in the little cubby of the trunk there are two silver screws attached to a black tab that is screwed to the trunk. The one on the left is where I bolted down the ground. So, should I take the bolt off and sand off the paint from that, or can I move that tab so that I can sand the trunk below that and mount the ground between the black tab and the trunk itself? Or, is there a better place to put the ground?

10-31-2009, 11:03 PM	#41 (permalink)
jrniehaus Base Member Join Date: Oct 2009 Location: Phx,AZ Posts: 45 Drives: 370z 6spd sport mdl Rep Power: 16	I didn't see where your ground was. Plus I haven't tried yet, but I don't know if I can get that black tap off of the trunk area to sand under it. It may, but I haven't tried yet.

11-02-2009, 05:14 PM	#42 (permalink)
jrniehaus Base Member Join Date: Oct 2009 Location: Phx,AZ Posts: 45 Drives: 370z 6spd sport mdl Rep Power: 16	Ok, so I actually moved the ground from the amp to a different bolt in the trunk and sanded it real good. Still have a engine buzz noise. Wondering if it is now the deck that needs to be grounded to the body somewhere also. I believe you grounded yours to a bolt near the gear selector? And my Hd 900-5 also seems to have a bit of a hissing noise when I set the input gains to the 24.6(fronts) and 44.7(sub) voltage levels. Maybe I should turn the amp gains down a bit to make the hiss less?

11-02-2009, 06:27 PM	#43 (permalink)
bigaudiofanat Car Audio Installer Join Date: Jun 2009 Location: Magnolia DE Posts: 8,342 Drives: 2012 Infiniti G37x Rep Power: 853	Who makes your head unit? If it is pioneer you might have to ground the rca plugs if you already grounded the unit to a clean place. 80% of the problems with noise are grounds that is why I keep bringing them up. And yes I say pioneer because they are known for this problem. Here is a thread that might help you out more. "Grounding the RCA's on the head unit Many have had problems with Pioneer head units because of a poor internal RCA ground. To remedy this, simply wrap wire around the RCA's and screw the wire down to the head unit's chassis like so:" http://www.caraudio.com/forum/showthread.php?t=198477 __________________ Need help with car audio or electronics? Let me know!! Need Help Let Me Know Direct email address reimermatt@gmail.com Owner of: Dynamic Mobile Audio Follow me below https://www.facebook.com/Dynamicmobileaudio/ Last edited by bigaudiofanat; 11-02-2009 at 06:30 PM.

11-02-2009, 06:31 PM	#44 (permalink)
bigaudiofanat Car Audio Installer Join Date: Jun 2009 Location: Magnolia DE Posts: 8,342 Drives: 2012 Infiniti G37x Rep Power: 853	Also if you still can not get it. Please contact me threw aim or yahoo so we can talk about the problem further. __________________ Need help with car audio or electronics? Let me know!! Need Help Let Me Know Direct email address reimermatt@gmail.com Owner of: Dynamic Mobile Audio Follow me below https://www.facebook.com/Dynamicmobileaudio/

11-02-2009, 06:38 PM	#45 (permalink)
SlikNik Enthusiast Member Join Date: May 2009 Location: Florida Posts: 294 Drives: 2015 Corvette Z51 Rep Power: 18	I have the same amp and just finished my install last week. No engine noise luckily. I ran rca's down the middle, power wire down the drivers side. New speaker wire from amp(under that black foam piece) to crossovers under the seats, to door components. When your wires start to get closer together as they get closer to the amp make sure they don't run parallel next to each other. If they have to cross each other I have always heard to cross them at 90 degrees. I used that bolt to the left of the remote sensor thingy that was talked about in another thread to ground my amp. Used a wire brush in a drill to clean it down to metal. The head unit is grounded to the wire harness on mine.

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