Heater blows cold air on 1997 Mercury Mountaineer

engine temp. is much higher than normal so i suspectd bad water pump but has no unusual noise, top radiator hose seems to have pressure. no leaks, fluid levels normal. appreciate any ideas. thx

1 answer 1 comment
poss stuck closed thermostat because you say u are not losing coolant
appreciate your help...i had thought they failed in open only. will try repcl and let you know. thx again, mo