Electronic Noise

Hey guys... what could cause a constant, and annoying electronic buzz in my 1993 5.0. The previous owner installed an aftermarket stereo, tach, etc, but I really don't think that is it.

The noise is constant when the car is on. Doesn't go away no matter what you do inside the car, not does it ever change.

So I'm thinking something under the hood. But I don't have a clue where to look or what to do. I guess I can replace the wires, plugs, cap, etc, but something tells me that ain't it. It's too constant to be related to speed/revolutions.

Anyone, anywhere, have this problem before?

Thank you.

Brad

"Brad and Karen" > wrote in
news:Olzlk.112852$kx.106779@pd7urf3no:

> Hey guys... what could cause a constant, and annoying electronic buzz
> in my 1993 5.0. The previous owner installed an aftermarket stereo,
> tach, etc, but I really don't think that is it.
>
> The noise is constant when the car is on. Doesn't go away no matter
> what you do inside the car, not does it ever change.
>
> So I'm thinking something under the hood. But I don't have a clue
> where to look or what to do. I guess I can replace the wires, plugs,
> cap, etc, but something tells me that ain't it. It's too constant to
> be related to speed/revolutions.
>
> Anyone, anywhere, have this problem before?
>
> Thank you.
>
> Brad

Maybe the fuel pump?

Try pulling fuses one by one to isolate the source of the noise.
Alternator , ignition noise usually varies with RPM though. Ignition noise
''pops'' and alternator makes a whine.
Noise in radio or in tape/cd mode? Radio noise usually comes in via the
antenna.
Good grounds to radio? Chassis ground to radio frame is important for it's
shielding. Check all the grounds especially the battery to frame and body.
Power to radio shouldn't be shared with a noisy circuit like the tach., fuel
pump, heater, etc. . Motor make electronic noise as well as the ECM
Most aftermarket radios I've had turn to crap after a the miles go on.


"Brad and Karen" > wrote in message
news:Olzlk.112852$kx.106779@pd7urf3no...
Hey guys... what could cause a constant, and annoying electronic buzz in my
1993 5.0. The previous owner installed an aftermarket stereo, tach, etc, but
I really don't think that is it.

The noise is constant when the car is on. Doesn't go away no matter what you
do inside the car, not does it ever change.

So I'm thinking something under the hood. But I don't have a clue where to
look or what to do. I guess I can replace the wires, plugs, cap, etc, but
something tells me that ain't it. It's too constant to be related to
speed/revolutions.

Anyone, anywhere, have this problem before?

Thank you.

Brad

Brad and Karen wrote:
> Hey guys... what could cause a constant, and annoying electronic buzz
> in my 1993 5.0. The previous owner installed an aftermarket stereo,
> tach, etc, but I really don't think that is it.
>
> The noise is constant when the car is on. Doesn't go away no matter what
> you do inside the car, not does it ever change.
>
> So I'm thinking something under the hood. But I don't have a clue where
> to look or what to do. I guess I can replace the wires, plugs, cap, etc,
> but something tells me that ain't it. It's too constant to be related to
> speed/revolutions.
>
> Anyone, anywhere, have this problem before?
>
> Thank you.
>
> Brad
>

Might be helpful to know where the noise comes from

--



From what I've seen you doing in nana.sightings this
month, I really must question your conclusions. Of
the roughly 4079 reports you posted to nana.sightings,
my favorite will remain your LART of the mail you
received from Cron, running on your own computer. - David Ritz

"Joe" > wrote in message
...
> "Brad and Karen" > wrote in
> news:Olzlk.112852$kx.106779@pd7urf3no:
>
>> Hey guys... what could cause a constant, and annoying electronic buzz
>> in my 1993 5.0. The previous owner installed an aftermarket stereo,
>> tach, etc, but I really don't think that is it.
>>
>> The noise is constant when the car is on. Doesn't go away no matter
>> what you do inside the car, not does it ever change.
>>
>> So I'm thinking something under the hood. But I don't have a clue
>> where to look or what to do. I guess I can replace the wires, plugs,
>> cap, etc, but something tells me that ain't it. It's too constant to
>> be related to speed/revolutions.
>>
>> Anyone, anywhere, have this problem before?
>>
>> Thank you.
>>
>> Brad
>
> Maybe the fuel pump?

most likely.
Just turn on the key a little not start, you should hear a short buzz as the
pump gets to pressure. if it keeps buzzing you may need to replace it.
Sound should be max in the trunk left side behind the tire, take out the
carpet to check.

Agreed on the fuel pump comments. My '93 has a buzz that is not a high pitch, but lower tone that is from the fuel pump in the back of the car. And as noted in the other post, just turning the key on without cranking the starter you will hear the the noise until the fuel pressure comes up and it will stop. Agreed that if it doesn't stop before starting the car you may have to replace the pump. But after the car is started you will hear the pump run continually because it's going to be working to keep the pressure up. Once when driving and I nearly ran out of gas I could here the fuel pump racing up and down as it was trying to pick up the little remaining fuel.

My experience with audio amplifiers is that many cheaper amps will buzz a lot, but again, if you hear the buzz just turning on the key and not starting the car then you may be onto something. Easiest thing there is just to pull the power on the amp and see if it goes away.

Good luck and let us know if you find it!

mC

Wow. Thanks for ALL the sugesstions guys. There's a lot here to look at. Stereo grounds to fuses to the pump. I certainly will look at all the above and let you all know in a week or two.

Thanks again everyone!

Brad

"mC" > wrote in message . ..
Agreed on the fuel pump comments. My '93 has a buzz that is not a high pitch, but lower tone that is from the fuel pump in the back of the car. And as noted in the other post, just turning the key on without cranking the starter you will hear the the noise until the fuel pressure comes up and it will stop. Agreed that if it doesn't stop before starting the car you may have to replace the pump. But after the car is started you will hear the pump run continually because it's going to be working to keep the pressure up. Once when driving and I nearly ran out of gas I could here the fuel pump racing up and down as it was trying to pick up the little remaining fuel.

My experience with audio amplifiers is that many cheaper amps will buzz a lot, but again, if you hear the buzz just turning on the key and not starting the car then you may be onto something. Easiest thing there is just to pull the power on the amp and see if it goes away.

Good luck and let us know if you find it!

mC

Brad and Karen wrote:
> Wow. Thanks for ALL the sugesstions guys. There's a lot here to look at.
> Stereo grounds to fuses to the pump. I certainly will look at all the
> above and let you all know in a week or two.
>
> Thanks again everyone!
>
> Brad
>

It'd be a lot easier if you figured out if it comes from the
speakers or not.


--



From what I've seen you doing in nana.sightings this
month, I really must question your conclusions. Of
the roughly 4079 reports you posted to nana.sightings,
my favorite will remain your LART of the mail you
received from Cron, running on your own computer. - David Ritz

Hey guys.

Pulled all the fuses tonight and that didn't help. It's also not the pump,
it starts then shuts down.

I took the stereo apart and noticed that the black wire from the stereo was
connected to the black/green wire on the car. Could this be the source of
the problem? Shouldn't that black wire go to a metal piece?

The grounds on the battery were good. This car has electrical stuff
everywhere. It obviously used to run a supercharger and there are more wires
for gauges and stuff that you can imagine, under the dash, in the engine
compartment. I just noticed a second set of wires coming off the plug to the
distributor. They are capped but I have no idea where they once went. The
whole car is like that. ARGH!

Thank you again.

Brad


"Repairman54" > wrote in message
...
> Try pulling fuses one by one to isolate the source of the noise.
> Alternator , ignition noise usually varies with RPM though. Ignition noise
> ''pops'' and alternator makes a whine.
> Noise in radio or in tape/cd mode? Radio noise usually comes in via the
> antenna.
> Good grounds to radio? Chassis ground to radio frame is important for it's
> shielding. Check all the grounds especially the battery to frame and body.
> Power to radio shouldn't be shared with a noisy circuit like the tach.,
> fuel pump, heater, etc. . Motor make electronic noise as well as the ECM
> Most aftermarket radios I've had turn to crap after a the miles go on.
>
>
> "Brad and Karen" > wrote in message
> news:Olzlk.112852$kx.106779@pd7urf3no...
> Hey guys... what could cause a constant, and annoying electronic buzz in
> my 1993 5.0. The previous owner installed an aftermarket stereo, tach,
> etc, but I really don't think that is it.
>
> The noise is constant when the car is on. Doesn't go away no matter what
> you do inside the car, not does it ever change.
>
> So I'm thinking something under the hood. But I don't have a clue where to
> look or what to do. I guess I can replace the wires, plugs, cap, etc, but
> something tells me that ain't it. It's too constant to be related to
> speed/revolutions.
>
> Anyone, anywhere, have this problem before?
>
> Thank you.
>
> Brad
>

Brad and Karen wrote:
> Hey guys.
>
> Pulled all the fuses tonight and that didn't help. It's also not the pump,
> it starts then shuts down.
>
> I took the stereo apart and noticed that the black wire from the stereo was
> connected to the black/green wire on the car. Could this be the source of
> the problem? Shouldn't that black wire go to a metal piece?
>
> The grounds on the battery were good. This car has electrical stuff
> everywhere. It obviously used to run a supercharger and there are more wires
> for gauges and stuff that you can imagine, under the dash, in the engine
> compartment. I just noticed a second set of wires coming off the plug to the
> distributor. They are capped but I have no idea where they once went. The
> whole car is like that. ARGH!
>
> Thank you again.
>
> Brad
>
>
> "Repairman54" > wrote in message
> ...
>> Try pulling fuses one by one to isolate the source of the noise.
>> Alternator , ignition noise usually varies with RPM though. Ignition noise
>> ''pops'' and alternator makes a whine.
>> Noise in radio or in tape/cd mode? Radio noise usually comes in via the
>> antenna.
>> Good grounds to radio? Chassis ground to radio frame is important for it's
>> shielding. Check all the grounds especially the battery to frame and body.
>> Power to radio shouldn't be shared with a noisy circuit like the tach.,
>> fuel pump, heater, etc. . Motor make electronic noise as well as the ECM
>> Most aftermarket radios I've had turn to crap after a the miles go on.
>>
>>
>> "Brad and Karen" > wrote in message
>> news:Olzlk.112852$kx.106779@pd7urf3no...
>> Hey guys... what could cause a constant, and annoying electronic buzz in
>> my 1993 5.0. The previous owner installed an aftermarket stereo, tach,
>> etc, but I really don't think that is it.
>>
>> The noise is constant when the car is on. Doesn't go away no matter what
>> you do inside the car, not does it ever change.
>>
>> So I'm thinking something under the hood. But I don't have a clue where to
>> look or what to do. I guess I can replace the wires, plugs, cap, etc, but
>> something tells me that ain't it. It's too constant to be related to
>> speed/revolutions.
>>
>> Anyone, anywhere, have this problem before?
>>
>> Thank you.
>>
>> Brad
>>
>
>

Okay, I'm only going to try this one more time. Where is this noise
coming from? Does it come out of the stereo speakers or from somewhere
else?

--



From what I've seen you doing in nana.sightings this
month, I really must question your conclusions. Of
the roughly 4079 reports you posted to nana.sightings,
my favorite will remain your LART of the mail you
received from Cron, running on your own computer. - David Ritz