OVERHEATS on 1995 Mercury Mystique

95 MERC OVERHEATS REPLACE THERM,REALYSWITCH,FLUSHE
RAD REPLACE FUSES IN BLACK BOX NOW FANS WORK GAGE WORKS
COLD AIR OUT OF HEATER AND STILL OVERHEATS GAGE GOES
TO RED

Asked by for the 1995 Mercury Mystique
4 answers
I had same problem
Merc made a water pump with a graphite impeller in the water pump.
This impeller, with age and heat, will break apart.
it will not be noticed from outside because the belt is okay and still turning
the pulley.
Meanwhile-inside the pump, there is nothing turning the pump.
Without circulation your car just overheats, but nothing is putting low through the heater core inside the car.
I thought it might be a plugged heater core, but found the water pump problem.
Aluminum impellers available but extremely expensive.
Are you sure you didn't install the thermostat upside down?
did you burp the system? you might have an air pocket. (the air pocke is what the temp sensor is reading or theres so much air that its not pressurizing)
it might be your temperature control switch