Vaper locking
Lets think about this some more.
Has the problem come about slowly over time, or suddenly after some event? Like after a repair, or a change in operating condition, or a change in fuel supply, like after filling up in a out of the way, low volume station, or even your regular station, as they could have gotten a load of out of spec vapor pressure summer fuel, or the out of the way station is still pumping low vapor pressure winter fuel, that's known to cause hot temp vapor lock.
Around here we hear of interstate folks from up north, traveling down south with a load of winter fuel, have the engine shut down while running hot in the surrounding mountains.
You could try ducting cooler fresh outside air at the problem under hood area & see how it goes.
EDIT: I believe you have a return type fuel delivery system that re-routs unused fuel from the engine compartment back to the fuel tank & that returning fuel has picked up engine heat & transferring it to the fuel tank, so if the tank is low on fuel, it'll get hot faster than a full tank & that can induce vapor lock, especially if you still have low vapor pressure winter fuel in the tank.
More thoughts for pondering, let us know what you find.










