My wife drives a 1991 Buick LeSabre with about 75,000 miles on it. For the past couple of weeks she has been complaining about a problem with her right directional signal. She says that the little arrow on the dash stays lit solid and doesn't blink when making a turn. I haven't had a chance to get the car into the shop until today, and of course now it works fine. Should I forget about it hoping it's fixed or should I bring it to my mechanic to see if he can find the problem even though it isn't happening right now?
Nothing fixes itself. As far as bringing the car in for repair now or later, do it now while you have the time. It's probably just a bulb gone bad or a poor connection at the bulb's socket. A qualified technician will be able to find it quickly, even though it's working right now, by means of jiggling and tapping at all the directional bulbs and sockets on the right side. When he hits on the correct one, it's gonna go out and the rest will stop flashing.
The reason behind the blinker not blinking is the fact that you lost a bulb (resistance) in that directional circuit. This reduces the amount of current needed to trigger the "flasher", and in turn discourages the "blink". The flasher is an on/off switch that opens and closes the circuit in a timed orderly fashion when the proper amount of amperage is flowing through it. The flasher could be the cause of a no blink condition if both sides were involved.
Why did it start working again on your day off? The most common cause would be a broken filament in a bulb, and when your wife hit a bump in the road just right on the way home that day, the filament touched its broken ends together and completed the circuit. This is exactly what happens when you have a headlight out and you give it a good shot with your fist and it miraculously comes back to life. It doesn't last, trust me. The cause may also be a poor connection at the socket, or anywhere else in the circuit, and still result in the same symptom. No blink.