AM Radio Static - Tilted Forum Project Discussion Community

Average_Joe · 09-17-2004, 03:12 AM

I bet this is an easy one for you experts out there.

The stock radio system on my '95 Ford Explorer works great except for loud static on the AM bands. I have noticed a few characteristics of this problem:

Engine on = lots of static, engine off = little to no static.
Engine acceleration increases static and humming.
Plugging in devices into the cigarette lighter causes major static.

I was told that the engine computer is the root cause, and that the wires are too close to the engine. My mechanic won't waste his time on it.

Is there a way for a non-auto expert (myself) to troubleshoot and correct this problem? How about manuals with diagrams and photos?

Nelson · 09-18-2004, 06:40 PM

Sounds like a bad ground - either at the radio or the antenna.

You can try and relocate the factory radio ground to another location - make sure its a chasis ground - not just any metal part under the dash. It may not hurt to relocate the 12V switched/ignition wire on the radio as well.

As far as the antenna goes - look for corrosion where the antenna is mounted on the under side of the fender (you may have to remove the antenna).

noblejr · 09-18-2004, 08:02 PM

When I worked at an install shop, I found a quick way to verify a grounding problem with the radio/antenna effecting the AM band is to put a piece of electrical tape over the outside (ground) of the antenna plug, and plug it back in the radio. If the radio dosen't work at all, you have no ground on the radio and it is grounding through the antenna wire. If it gets rid of the problem, then you need to inspect the ground for your radio and the antenna. After hours upon hours of work, if you still can't seem to get it to work correctly, you could leave the tape covering the outside of the antenna plug, but it will hurt your overall reception, even though it gets rid of the power interference in AM.

kazoo · 09-25-2004, 04:00 PM

After you've looked at grounds, the next places to look are alternator noise and ignition noise. Suppressor capacitors can be had at Rad Shack-they're reasonably cheap. Install one on the alternator and see if it makes a difference. Ditto for the ignition system. Lastly-are you using resistor-style spark plugs? If all else fails, power line noise suppression kits can be installed to clean up the 13 volts going to your radio.

Charlatan · 09-25-2004, 04:21 PM

Sit back and enjoy the static... part of what you are hearing is left over from the creation of the Universe... I know... but it's cool information.

09-17-2004, 03:12 AM	#1 (permalink)
Average_Joe Psycho Location: Under the Radar	AM Radio Static I bet this is an easy one for you experts out there. The stock radio system on my '95 Ford Explorer works great except for loud static on the AM bands. I have noticed a few characteristics of this problem: Engine on = lots of static, engine off = little to no static. Engine acceleration increases static and humming. Plugging in devices into the cigarette lighter causes major static. I was told that the engine computer is the root cause, and that the wires are too close to the engine. My mechanic won't waste his time on it. Is there a way for a non-auto expert (myself) to troubleshoot and correct this problem? How about manuals with diagrams and photos?

09-18-2004, 06:40 PM	#2 (permalink)
Nelson Tilted	Sounds like a bad ground - either at the radio or the antenna. You can try and relocate the factory radio ground to another location - make sure its a chasis ground - not just any metal part under the dash. It may not hurt to relocate the 12V switched/ignition wire on the radio as well. As far as the antenna goes - look for corrosion where the antenna is mounted on the under side of the fender (you may have to remove the antenna). __________________ Nelson

09-25-2004, 04:00 PM	#4 (permalink)
kazoo Psycho Location: Where the night things are	After you've looked at grounds, the next places to look are alternator noise and ignition noise. Suppressor capacitors can be had at Rad Shack-they're reasonably cheap. Install one on the alternator and see if it makes a difference. Ditto for the ignition system. Lastly-are you using resistor-style spark plugs? If all else fails, power line noise suppression kits can be installed to clean up the 13 volts going to your radio. __________________ There ain't nothin' more powerful than the odor of mendacity -Big Daddy

09-25-2004, 04:21 PM	#5 (permalink)
Charlatan Getting it. Super Moderator Location: Lion City	Sit back and enjoy the static... part of what you are hearing is left over from the creation of the Universe... I know... but it's cool information. __________________ "My hands are on fire. Hands are on fire. Ain't got no more time for all you charlatans and liars." - Old Man Luedecke

09-18-2004, 08:02 PM	#3 (permalink)
noblejr Crazy Location: Atlanta	When I worked at an install shop, I found a quick way to verify a grounding problem with the radio/antenna effecting the AM band is to put a piece of electrical tape over the outside (ground) of the antenna plug, and plug it back in the radio. If the radio dosen't work at all, you have no ground on the radio and it is grounding through the antenna wire. If it gets rid of the problem, then you need to inspect the ground for your radio and the antenna. After hours upon hours of work, if you still can't seem to get it to work correctly, you could leave the tape covering the outside of the antenna plug, but it will hurt your overall reception, even though it gets rid of the power interference in AM.