Normal operating temp

A couple of things. The 2001+ V6 uses a CHT instead of an ECT. One of the MAIN reasons why Ford made this change is because the V6 is bad about trapping air inside the coolant jacket. This makes the ECT read low as well as blocking the flow of coolant.

Soooooooo the temperature as reported by the PCM is from the Cylinder head temperature sensor. Not from the coolant temperature sensor.

First thing. Double check there's no air inside the coolant jacket. If not, then straight up temperature is OK.

V6 coolant refilling procedure

Next thing. The 2001 V6 cooling fan is protected by a circuit breaker. This means that IF the cooling fan is drawing too much power it's possible for the CB to trip and thus disable the cooling fan. The CB will automatically reset after it cools down. This offers an explanation how the problem can come and go. Suggest spinning the fan by hand. How does it feel? IF there's binding or bearing roar consider replacing the fan.