Stopped for flowers at my neighbors farm and went out cutting with one of his daughters and left the car running with door open. When I returned (5 min?), car had turned itself off key turned to on position (pre ECU car). Returned key to insert position and turned to on and started and drove away. Did not think of it till at work. Has anyone else experienced? Was it he door open running or just sitting that caused auto shut down? Will have 100k mile report soon.