I had the same problem with my 94 Bonnie would just be driving down the street and wham she shuts off like you turned the keys off no warning. I got my crank sensor and my O2 sensor replaced and so far no stalls and no weird running so far its been a week now so look into those areas. That might just be your problem. Good luck and let us know. My tech guy said what happens is the crank sensor that'* going bad would get to hot and then it would not signal the pcm for spark into the motor and therefore the car would should off is what he said. I replaced it so far and no more shut offs yet.... I know this is scary because I was cruising down the hwy at 60 mph and she just quit yikes. Next morning I got a new Crank and O2 and so far its helped out alot.
1994 SSEi Fire Red New License plates soon BURNT 94