my 2006 mountaineer runs up to operating temp, and I don't have any heat.
Yes, well it would appear as though you have got a stuck thermostat (your engine does)~
you may have a pugged heater core too---see if the diverter valve which switches the core on is functioning normally....have someone move the lever and watch what moves...it will be along the firewall....unless it's the other side of the firewall....but make sure this HOT control works~ (cable operated)~
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