I have a '97 F150 V8/4.6. When I turn the headlights or parking lights on, I get terrible AM radio interference. Any ideas on how to rectify the problem? It's a new development - the AM used to be pretty good, but over the past month or so it has decreased sharply in quality. Then one morning I get ready to go to work, and the lights seem to cut into the AM signal. HELP!!! I have to hear KDKA in the morning to get going!!

Natedog

 

You can put filters on various parts to cut the noise. Start with an antenna filter (best buy, circtuit city, about $10). Your ant wire plugs into it and it plugs into the radio. If that doesn't take care of it, then you can put a filter on the power wires to the radio. Filters cost from $10 to $20 or more depending on how heavy duty of a one you get. I suggest putting one on the accessory power wire and the constant (battery) wire. They have 3 wires-1 for the wire from the power source, 1 going to the radio, and a ground. That should take a chuck of the hum out.

 

This problem can be fixed by replacing the antenna cable, you will find that it has corrosion.
Suggest going with Ford OEM cable since after market will likely be too short even though they say compatible.

Yes, I did the whole filter route until I found the solution, hope this helps someone in the future.

 

You also have have lost your grounding straps between hood and frame, trunk and frame etc. Also maybe the capacitor on the alternator may be compromised. It the static a buzz that whines up and down with RPM's? Could be the alt armature may be worn and/or brushes worn down to the wires.

None of the auto companies seem to bother with noise suppression anymore. They think everyone listens to FM.