96 starving and overheating

Last night a friend of mine took his 96xj 4.0 auto out for a trail run. I tailed behind him and it seemed for every 100-300 feet it would starve out of fuel it sounded and bog down. His fix was to purge the fuel rail and restart (still sounding like spit) and drive away. Now about an hour into the drive he hits steam and overheats as his efan will not turn on. Just wondering if anyone has ran into this fuel issue before? It seems like when it heats up it builds alot of air in the fuel system.

test the fuel pressure with a gauge.

Fuel could be boiling in the fuel rail, expecially with the winter formulation and ethanol added.

After he burped the fuel system it runs fine till the air builds again.

It smells like a fuel delivery problem of some sort. I would perform some comprehensive fuel pressure testing, including checking out the fuel pressure regulator....

It a cooling system issue that affects the fuel delivery. Welcome to vapor lock city.

Service the cooling system: coolant, thermostat, radiator cap, fan clutch, at the minimum. Install new hoses and water pump if needed. Fix the e-fan so its works. Consider adding hood vents.

A properly cooled engine shouldn't boil the fuel in the fuel rail.