94 Grand Voyager fuel issues after 2hrs

My mother-in-law has a 94 Grand Voyager with a 3.3L MPFI V6 FWD. Problem is after around 2 hours of straight driving the van will begin to stutter and shake with a loss of power.

Also at this time, if I go to put gas in the car, the gas nozzle will auto shutoff as if the tank is full with only putting in a very small amount of gas.

I don't know if it is related but the fuel gauge also has problems, sometimes it drops the empty with even half a tank left.

If I turn the car off and allow it to sit for awhile, The stuttering problem disappears.

The gas guage will sometimes fix with just turning off and restarting the vehicle

Any help would be very appreciated

Not too familiar with 2nd generation vans but I'll try.

Shooting from the hip I'd guess the pump is failing. Next time it starts stumbling connect a fuel pressure gauge and look for 49 psi. An easier test would be to keep the tank at least half full all the time. Fuel acts as a coolant for the pump. If your 16 year old pump isn't emersed in fuel it could heat up and fail. If you try this and the problem stops - change the pump or if you feel lucky, press on. Changing the pump would take care of the fuel indication as well. The sender is part of the pump. Could also be the pressure regulator. I believe on your 94 it's on the fuel rail.

SLow fill ups could have something to do with a vent, the EVAP system, or a check valve.