my 910 nissan bluebird was driving fine all morning, but when switched off for approx. 15 minutes, but when I turned the key both the oil & battery lites came, so I turned the keys to the off position, the lights were still on & the engine began to revv out of control and with a cranking noise. okay I popped the hood the negative terminal was smoking with arcing noise so I disconnected battery, saw an expose wire near the new coil that an electrician hook-up the day before. so i tried hooking battery but I got arcing from terminal and the cranking noise. got a mechanic to come but before even popping hoop turn the keys vehicle start purring good no noise or arcing, checks still done nothing found, any ideas out there

I'm shooting in the wind here but it sounds like the ignition switch was stuck on the cranking position some vehicles have a metal rod that goes from the switch to a spring activated module some times the spring sticks. thats on most of the older cars.