Bad water pump , problem with engine cooling fan ( if it is actually running hot
and not a problem with the gauge or sending unit )
check the heater core stopped up radiator
Check the radiator fan operation.
Waterpump, thermostat, radiator, radiator hoses.
It is on the passenger side of the engine bay between the radiator and engine. it is housed in a assembly in the radiator hoses. find the lower radiator hose at the radiator and follow it to a housing that connects the radiator hoses. The thermostat is in side
Rod your radiator and check your fan clutch or electric fans if you got them.
your thermostat is inline with your radiator.. its in a junction coming off the bottom radiator three hoses plug into it.
It may have an air lock in the cooling system The head gasket could be failing or the gauge may be showing the incorrect reading ,
The thermostat is not in the lower radiator hose of a vehicle. Thermostats tend to be placed at the end of the lower radiator hoses, not inside them.
on a 1993 4.9 it is just to the left of the thermostat where the radiator hose and heater core hoses go into the thermostat it has a couple of wires running into it.
if your radiator is in good condition with no leaks from hoses then i would recommend removing the thermostat out then place the thermostat housing back on top up coolant a check your flow by removing cap from radiator. If flow is good then it sounds like a blown head gasket.
2 radiator hoses / the top radiator hose comes from the engine thermostat / and the bottom radiator hose returns to the engine water pump
Try replacing the radiator fuse relay