Engine noise in radio.

[Itkix]

Has anyone ever heard engine whine through a aftermarket radio but factory speakers, Ive heard it through an amp with sub but never like this and it comes and goes. I bought car used with it like this I pulled radio out and it has a wiring harness everything appears to be ok, the guy did put in another ignition (key) switch wonder if that could have something to do with it. Like I said it comes and goes and somtimes its really loud. It has the mach system 1994 Gt. (Loose wire,Ground)

 

[earleys94gt]

I have heard that an aftermarket coil can cause noise in the radio, does your car have an aftermarket coil?

It is possible, like you said, that the new ignition might have something to do with it...but I would double check to make sure that all the grounds are good on the radio harness.

 

[Itkix]

Yes it does Msd coil.

 

[earleys94gt]

Yeah, I have heard the MSD coils can cause noise. Not sure if it is because of the model of coil, or maybe because of the ignition set-up.

If you have the stock coil, or have access to one, try swapping them and see if the noise goes away.

 

[toyman]

Has anyone ever heard engine whine through a aftermarket radio but factory speakers, Ive heard it through an amp with sub but never like this and it comes and goes. I bought car used with it like this I pulled radio out and it has a wiring harness everything appears to be ok, the guy did put in another ignition (key) switch wonder if that could have something to do with it. Like I said it comes and goes and somtimes its really loud. It has the mach system 1994 Gt. (Loose wire,Ground)

First question. Has the hood blanket been removed? Yes = noise, if no, is the grounding strap by the passenger side hood hinge secure?

I'm running aftermarket coil and a spark enhancer and noise is minimal. However, with the hood blanket removed there is only noise. The blanket has a foil liner on the hood side as the hoods are a composit material.

 

[Adam95GT]

Check the little thing on the coil bracket.... and the ground in the kick panel.

 

[Adam95GT]

Also did you bypass the mach 460 amps... IIRC the speakers are 6ohms... and dont work well with an aftermarket head unit.

 

[Itkix]

And one more thing sometimes when I have the radio volume all the way down I can hear a loud buzz through speakers with key on engine not running so I just turn radio off.

Have aftermarket hood, fiberglass do not see a grounding strap on passenger side hood latch nore do I see one hanging around anywhere.

Appears the diode?? on the coil is ok and is plugged in, I'll have to check the ground on the inside (is it behind drivers kick panel), and looks like the factory amps are being used.

 

[99FiveOh]

I have the same problem with my car.

As for the Mach 460 speakers, it makes no difference what impedence they are as long as you power them with the factory amps.

And which kick panel are you referring to, driver or pass? I'll trace it down and check it.

If I can't get it fixed soon I'm just gonna get one of those little noise suppression boxes, that should take care of it for sure.

 

[Adam95GT]

Posted via Mobile Device

think its in the driver kick pannel ill have to check when i get home but i know people have had problems running stock amps with an aftermarket head unit

 

[toyman]

And one more thing sometimes when I have the radio volume all the way down I can hear a loud buzz through speakers with key on engine not running so I just turn radio off.

Have aftermarket hood, fiberglass do not see a grounding strap on passenger side hood latch nore do I see one hanging around anywhere.

So there is no hood blanket, is that correct? Stock hood is a composit material (fiberglass?) and you will require the shielding to eliminate engine noise. The strap I was referring to goes from the liner foil to the inner fender at the passenger side hinge.

Appears the diode?? on the coil is ok and is plugged in, I'll have to check the ground on the inside (is it behind drivers kick panel), and looks like the factory amps are being used.

That's a capacitor mounted on the coil bracket.

 

[Itkix]

No hood blanket ,no strap.

 

[95Vert383AOD]

Ground Ground Ground....

1st give the radio its own dedicated ground! I never liked using factory grounds.

2nd The grounding under the hood is horrible. Get a short negative cable that already has the wire on it. Bolt that straight to the radiator support. Then put Ring terminals on the other grounds and bolt that to the radiator support.

side thought...You'll notice the engine block has a thicker ground to the battery than the chassis ground to the battery. That is the problem.Your radio is grounded to the chassis that has the smaller ground.

Rule #1 of car audio is that the negative wire must be equal or greater in side than the positive.

While you're doing that make sure you clean up the ground on the radiator support (sand it). Also some dielectric grease in the terminal you're bolting to the support wouldn't hurt.


If that doesn't work then its the factory amps.

Chris

 

[99FiveOh]

You know you might be right in my situation because when the noise starts coming through I can turn the radio all the way down and it's till there.

However, there is 2 different noises I'm hearing. One is like a constant noise that kinda disappears with engine RPM and the other is a ticking noise, like a plug wire is arcing somewhere, but I haven't found any wires to be damaged.

 

[Itkix]

Yea Mark mines the same way I'm gonna give the indash ground wire its own ground first and see what that does.

 

[99FiveOh]

let me know how your project goes. I gave up because i had other things I had to do with the car. But it's annoying so I'd like to get it fixed.

 

[Itkix]

Update:
I pulled the radio out today and looked at all the wires, I gave the ground its own grounding point didnt help, so with the key back and radio turned down I was still getting a buzz noise so I unhooked the speaker wires and still hear buzz, so I turned radio off and buzz went away, so I figured it had to be in the factory amps, so I checked all power wires and found whoever hooked the factory amp turn on to the red 12v wire and was creating the buzz, I put that wire to the radio remote turn on and no buzz now, but I havent driven the car yet so will see, but noise gone for now.

 

[99FiveOh]

well, I installed my own stereo after I got my car and I ran all the wires properly with the amps being turned on with the remote wire from the head unit and I still have the problem.

I'm going to swap in a new set of plug wires to see if maybe I have one arcing somewhere.

 

[Itkix]

Well maybe me moving the ground and the power wire both did the trick, I hope it's fixed, I had a plug wire arching one time and it ran like crap, I didnt know what it was and while messing around one night I saw it arching. So I dont know if its a plug wire.

 

[94cobra#519]

ditto! i had the same problem except its only when i play the radio not cd or tape.