I'm Having Problems With My 87' Ford F250.Cant Figure It Out.?

for the age of the vehicle, check the pull up hose for the fuel pump in the tank. also check the fuel pump. if the fuel pumps are electric and are still from the factory, they would be 23 years old. they may need to be replaced. also if the tanks are steel, you could have some rust inside of the tank and the rust is clogging up the fuel pump or fuel pump line going to the engine. there also may be a bent in the line causing the engine to not get fuel.