i have a 67 rs/ss with a big block in it. the headlights work fine. doors open and shut no probs. the emergency flashers work. i can give a left or right signal and the light lights up but will not blink. i can hit the brake pedal and and they light up. pull the parking lights on and they work. it just doesn't work when i signal (they just sit there brighter but do not blink). i have changed the flasher on the fuse box. checked all the bulbs. rechecked all the grounds and they are good.