01 Impala LS stops running - cannot find the problem

2001 Chevrolet Impala 3800 Problem: My car stops when running as if the key were switched off. I can bring the car to a halt, put in Park and start up immediately - no hesitation or delay. There is no obvious connection to the problem. It stops when cold or hot - in motion or idling - sometimes it fails to fail (like the almost three days it was with the mechanic). There are NO error codes or Check Engine lights. The Ignition Control Module and Crank Position Sensor have been changed with no luck in solving the problem. A container of gas treatment was added after the first time this happened, so it isn't bad gas. It doesn't appear to be the fuel pump of fuel filter since it starts back up right away. The car has aprox 122,000 miles on it and I'm the original owner and have not had a problem like this before. :banghead: Any knowledgable assistance would be appreciated by both my technician and myself - especially me since I'm stuck without my car. Thanks in advance for your assistance. :smile:

Welcome to AF, seen this with someone that had a load of stuff on their key chain! Possible bad ign. switch or connectioon to it among about 20 other possibilities, no quick answer here.

Nothing but the fob with the key - nothing, but I'll add the ignition switch circuitry as a possible cause.

The MASS AIR FLOW SENSOR seems to have been the problem. After changing it out I've gone 90+ miles w/o a stall.