This interference correlates directly to tire rotation speed, engine rpm has no effect. Under about 5mph it won't make the noise, but over that you hear a pop more or less for every rotation of the tire and when you hit say 50mph it is just a steady static noise on AM only. Haven't pulled the head unit yet, checked several body grounds under the hood and all are good. Don't know if a damaged wheel sensor could cause an issue or not.

 

Which one of your vehicles is having this problem? Perhaps posting your question on another forum may get you more help.

 

It may as the Ranger side seems to be very unhelpful/dead. I figured "2001 B4000" was pretty obvious on what the vehicle is especially when it is placed in the Ranger/B series area.

 

.......patience, grasshopper......

I say pull the radio out and look over the antenna cable connection. And then check the antenna side.

There should be a "radio ignition interference capacitor" attached to the coil pack. Is it there? Maybe try re-attaching it or even replacing it.

Also, keep in mind this: TSB 01-7-3

 

Sorry about that. I looked at your vehicle list in your post and not the heading. Fortunately Rockledge gave you good help.