Here's a bizarre one ,Stock 12 A with clean tank/filter/pump new/ good fuel flow /carb clean/burning nicely.

I drive for say 60 miles on highway all's well- then car bogs down /cuts out .it happens often .Leave it for say 5 minutes then starts up all okay for another few miles then cuts out again.

Can't suss problem -it's like when something warms up it's causing cut out or blockage -I could hear relay clicking as I drive.
Anyway I looked at the fuse -15 amp -which feeds ignition/relay -says METER in fuse box cover and found that the fuse had like gummy stuff and dust on the pins.
Could this be what was heating up and blocking current flowing thru the circuit to supply constant voltage to the fuel pump ??? then cooling down to allow starting .
Anyway cleaned all fuses and box -took it for a good run -not 60 miles and all seems okay!
Anyone else experience this " Dirty Fuse Syndrome" ?

 

not one I've run into personally, but certainly within the realm of possible causes.

Corrosion - > resistance - > heat - -> corrosion cycle is a well-known problem with connectors, no reason why a fuse connector should be any different.

 

meter fuse is for the gauges, but i have run into dirty fuse problems. its not a bad idea to pull em out one at a time and put em back once in a while

 

Fuel pump power doesn't go through the 15 amp meter fuse. It is protected by the 20 amp fuse marked engine next to the meter fuse. If you still have emission control check this hose carefully. Hole can open when warm and seal up when cold. When its open it creates a large vacuum leak.
https://www.rx7club.com/1st-generation-specific-1979-1985-18/hose-question-750125/

 

From the symptoms it sounds like you still might have debris in the tank that's getting sucked up and blocking the pickup tube. Once the engine stops, gravity pulls the fuel back into the tank clearing the blockage. Another possibility may be something overheating in the ignition system, coil or igniter, poor electrical connection.

 

I'm with Trochoid-
you are describing the exact symptom my 80 SA had, caused by tank sheddings plugging the outlet (and sometimes the fuel filter): car stalled. Sat. Started 5 min later then repeat...
Pulled tank, chem-dunked, re-lined tank w POR15 gas tank kit. Prob solved.
Stu Aull
80GS
Alaska