Radio problem, static when engine running

[MikeWasHere05]

This started a few days ago, it came with the slew of other problems.

When my car is in accessory the radio comes in perfectly clear. When I start the car, I have a static whining noise that seems to get louder as RPMs rise. The CD players comes in perfectly clear.

Last year I had a signal booster (not sure the technical name?) installed, it was like $20 installed so it isn't anything fancy, but it gave me reception when I had none otherwise. I had the place that installed it check it out for me today, they replaced it and it didn't fix the problem. They said it might be a bad ground on the antenna, but why does the static only appear when the engine is running?

Ideas?...

[speedydragon]

my "diversion box" or whatever it was called went bad on me this past christmas. It would go staticy when the temps were warmer.

[Squarrl]

well that is box is just an amplifier of the signal to the radio. What you are hearing is the EM from the cars electrics. In home audio what you would do is isolate the source radio from amp to get rid of the humm generated by the mains. what you can do to fix this is get an antenna that is better, run the box on a different circuit from the radio or possibly run ferrite cores on the stereo/amp power lines.