Driving our 1980 GT at night the engine began missing. Turning off headlights the engine ran fine till I could stop. Parked, the engine idled OK with no lights, but when headlights were turned on the engine died. It seemed that low voltage was the problem, as the fuel guage read empty when tank was actually 1/2 full, radio stations reset, and the lights were dim and the engine would not crank.

After about 30 minutes, I tried again and the car started with no trouble and has run normally since then (except that the idiot lights no longer work). Alternator charges 13.8 volts, brushes are not too short and all the belts are fine.

What happened?

NatSmith