91 F-150 stalls when hot
My '91 F-150 5.0l has an erradic problem of stalling when it gets hot. It seems to occur most often when I have driven at highway speeds for an hour or so. It will start by "chugging" intermittently and then seems to get worse. It will power out but if I switch off the OD I can maintain a speed of 35 mph or so but can't get back up to speed. If I stop it will run really rough and stall out and then won't start back up. ONce it has cooled down for several hours it will restart and seems fine. I have checked numerous things but don't want to start replacing without a more definitive direction.
New plugs, wires cap, rotor, alternator, fuel filter and fuel pump relay.