Radio noise on Am

[Butchieee]

1999 Explorer-Getting a lot of radio whining through radio on Am. Rotating the heater temperature control knob changes the frequency and at certain positions it goes away. Also getting a lot of spark plug ignition noise. Was going to change the radio suppression capacitor but can't seem to locate it on my 1999 Explorer 4.0 SOHC engine.Any advice on these issues.I read all the info on this site about fuel pump noise but I don't think thats it. Thanks in advance.

 

[Donner]

Hey there... so I guessed right. You gotta stock stereo? How's the connection between the antenna plugs?

 

[Butchieee]

Radio noise

The antenna seems to be fine. I pulled the unit and reseated everything.
Does anyone know where the radio noise supressor cap is thats under the hood buy the coil.Can't seem to find it. I have the CD on the Explorer that shows the location and when I do find it my mothers words will come back to haunt me. She used to say (if it was a snake it would of bit you).Thanks

 

[Donner]

My mom says the same thing... Central American version: If itwas a sneck, ita bit cha' rass!

My stereos do that from time to time, but it usually only lasts a few minutes. This is a good site to check/ask about oem if you don't get an answer... (they're not open, but just in case).

http://oem-auto-accessory.com/factory_ford_radios.html