The tweeters in my C-pillars used to whine in sync with the engine RPM. One guy thought I had a turbo or something. I ended up moving my wiring to the tops of the doors instead of running them under the doorsills. That fixed it for me.
1996 Contour "Mean Green" (99-02) 2002 Malibu Blue Focus ZX5 - something to hold the PB 15...
