2000 cv engine whine over speakers

I have a 2000 c/v. when i start the car i'm getting engine whine over the speakers mostly AM, and it's interfereing with reception on AM & FM. Local channels aren't as bad as distant stations. I changed Radio with very little help. when antenna wire is unplugged from rear window it gets worse. I cheked for antenna module that I saw in other posts but my car doesn't have one that I could find. Does anyone have any other ideas on what to check. I know on older cars there was a capaciter on the coil to remove engine whine from radio, anything like that on new cars?