We have a 1996 Nissan Quest - but only 72000 miles (we bought it from our daughters’ 90 year old piano teacher who only used it for camping trips with 45K miles 3 years ago) I have an intermittent stalling problem. Only at low speed, sometimes going up hill or into a turn, but it’s also happened going straight on, I get a compete loss of power. Still have steering, (not power) so I wrestle the beast over, and it restarts right away. No check engine light. This has happened about 6 times. Not low gas level, usually 1/2 + tank. No codes.
My two prime suspects would be a bad crankshaft position sensor or a gunked-up Mass Airflow sensor.
However, I am amazed that the CEL isn’t lit up. Are you sure that the CEL still works?
When you turn the ignition key to the start position, does the CEL light up temporarily?
In any event, you need to seek a good mechanic, as stalling on the road can be a safety hazard. If you don’t know of any good independent mechanics in your area, I suggest that you use the Mechanics Files link at the top of this page.
I would suggest fuel pump. If I read it correctly, you said the electrical is working but the engine stalls. Is there any regularity to it? Could be a crank or cam sensor. It’s hard to tell, but fuel pumps can be intermittent. A gauge could be place on it and monitored.