I used to see (i.e. hear) the same effect with an older car which I upgraded from mechanical points to a jerry-rigged EFI system. When I turned on the car, it w

I used to see (i.e. hear) the same effect with an older car which I upgraded from mechanical points to a jerry-rigged EFI system. When I turned on the car, it would have a distinct clicking sound that came through the radio as the coil fired.