i did this to mine and i have leds and only the passenger side blinks with lights on and off but the driver side only blinks with lights on or only with lights off depending on the way the bulb is turned i've switched the bulbs and still does the same thing it works properly with a standard 194 bulb maybe its because i haven't gotten a led flasher for it yet
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99 grand prix gt 130,000 miles zzp computer custom catback PRJ wires sprint springs ss grills Speedbuilt intake, HV3, HF throttle body, throttle body heat shield, powerlog,f/r GMPP Swaybars MSD coils, Speedbuilt diagnal braces, f/r strut bars Zex Nitrous, and much more.