No gas smell, no codes, and the ODBII data appears to be within tolerances. Only exception is the two voltage readings in Torque. One says 13.1v (voltage) and one says 12.5v (voltage command module).
I keep telling her to get a new battery.
It's a very intermittent issue. It happened 5 times on the highway with cruise on the way to San Antonio, 3 times on the way back. Car was filled before leaving Corpus and again before leaving SA. It hadn't happened again till today while driving to Portland over the harbor bridge.
Voltage while the engine is running will not normally be affected by the battery charge. And, since the battery is wired in parallel with the rest of the car's electronics, once the engine is running most cars will allow you to remove the battery with no affect whatsoever on the engine.
13.1 volts is a little low for a running engine, but not so much as would make me feel that something was wrong with the charging system. The voltage at the command module is most likely regulated, so that's not an indication of low system voltage, it's just what the regulator for the command module steps down the alternator voltage to in order to keep things acceptable for the command module.
In my experience, unless you're buying gas from "bubba's home-brew gasohol station," "bad gas" is just not a thing that happens. Between the overall quality of current name-brand gasoline and the frankly amazing ability of modern EFI systems to adjust to variances in fuel quality there just plain aren't the same sort of issues that people used to get in the 1960s with carbureted cars.
Similarly, I also doubt that the issue is with the key. Generally even cars that have an RFID chip in the key only validate at startup. If they lose communication with the key while the engine is running, they still keep running until they are manually shut off with the key like normal (but they won't start again if they cannot communicate with a key). This is done for safety. It's just not safe to have the system kill the engine intentionally and the engineers design the system failure modes accordingly.
What does seem possible is either a dirty MAF sensor causing problems with fuel metering on acceleration (though this would usually trigger a "check engine" light) or a fault in the electrical portion of the ignition switch. The latter would be especially possible if your mother has a large number of things on her keyring; if there's enough weight on it, acceleration could cause the keyring to pull on the ignition switch enough to cause a discontinuity if the switch itself is marginal to begin with.
Leaky or faulty injectors tend not to be intermittent and usually cause rough running pretty consistently, not a random cut-out. Similarly, a bad fuel pump or fuel pump relay would generally take longer to "reset" than a half-second.
The first thing I'd try is cleaning the throttle body and the MAF sensor. After that, I'd want to check the electrical portion of the ignition switch.
ZV
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