Nice car! I was a mechanic for the Pa State Police for thirtythree years "retired in 2008" and know all about the Crown Vic interceptor. A couple of common ailments, wont idle, replace the "idle air controll "cheap and easy". Any power window problems replace the drivers door master power window switch, "never had a window motor fail". Transmission and alternator at 60 to 70K "perhaps police use only?". If you lose your low beam headlights replace the lamp controll module under dash just right of steering shaft. Blower motor only runs on high, replace blower motor resistor, under hood behind the right cylinder head on firewall, "a real pain to get at". Engine missfire code set, replace the "over spark plug coil pack" on the offending cylinder. These Crown Vic's really hold up to "not my car" police use, enjoy yours!

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Stay safe people!