Popping noise on FM radio only

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=35965
Printed Date: May 14, 2024 at 8:57 AM

Topic: Popping noise on FM radio only

Posted By: kenmci
Subject: Popping noise on FM radio only
Date Posted: July 21, 2004 at 6:47 PM

I just installed a stereo into a 1995 Nissan Sentra, the harnesses had been cut off, and there are only 2 speaker, front door, that are hooked up behind the deck. My problem is that there is a popping noise on FM only, AM and CD sound fine. I have

regrounded the deck,
ran power wires directly from the ignition harness
wired the deck constant
hooked up a new antenna
disconnect all speakers from the car and used a test speaker
bench tested the deck

If the deck was in the car it makes the popping noise, but when the deck was bench tested it worked fine, even when I used the same temporary antenna that I used to check the deck while it was in the car. The car's voltage reads 13.6v while it is running and 12.76v when it is not. Any suggestions would be great because i have idea what to do.

Replies:

Posted By: StlS_Ron
Date Posted: July 21, 2004 at 6:52 PM

I have no idea but is the deck hitting something when installed in the car ? mabey a metal bracket. Once Again I dont know.

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Ya my radio sucks.
Oh by the way I cant spell!!!

Posted By: DYohn
Date Posted: July 21, 2004 at 7:26 PM

Does it pop when the car is off or only with the engine running? If it is only with the engine running, I'll guess you have a noisy engine ignition system or a bad engine ground strap.

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Posted By: Ravendarat
Date Posted: July 21, 2004 at 7:41 PM

You replaced the antena but did you replace the antena wire. Mabye you have a bad cable or mabye even just a bad end at the radio. I am gonna bet money on that cable if you havent replaced it yet

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double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer

Posted By: sparkie
Date Posted: July 21, 2004 at 8:29 PM

Popping noise on FM is usually from a fault in the ignition system. If the noise is only evident when the engine is running, then you should have your ignition system checked. It is usually do to dirty contacts in the distributor cap or faulty spark plug wires. What you are hearing is the high voltage, arcing across contacts. If the noise is independent of the engine, then something in the car is emitting the noise and the radio is picking this up either through the antenna or the power wire.

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sparky

Posted By: kenmci
Date Posted: July 26, 2004 at 1:28 AM

Thanks for all the feedback, i finally got the time to look at these posts. My first feeling was the ground on the battery, but i wouln't have thought of the engine ground.

To Stls_ron: it does it when the deck is sitting on the seat.

To Dyohn: it only makes noise when the car is running.

To Ravendarat: I tried replacing the antenna, and cable.

Again thanks to everyone for all the input. Also sparkie, I told the customer to see about having his ignition system checked, but thanks for the heads up, i'll let him know if he ever comes back.

Posted By: dudek38
Date Posted: July 30, 2004 at 11:19 PM

ive seen the same problem on ford trucks 1997 on AM only. major noise when vehicle is on and use of turn signals. ground loop problem?

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owner of
Motion Marine & Car Audio
the florida keys