my wife's taurus is having heater issues, ive tried flushing it out but still am not getting much heat out of it. worked fine last winter. the hoses on the heater core are both hot with the outlet hose not quite as hot. poured some liquid plumber into the core and let it set for 15 min then flused out both ways with a hose into a 5 gallon bucket, filling the bucket both times. saw no deris and it seemed to flow freely. was wondering if anyone with a taurus has had a similar issue. ive looked under the dash and the only door i see is the vaccum controlled blend door that moves when the floor-mix-defrost **** is turned. is there another door somewhere the may not be opening? fan operates in every position. i am thinking about putting a valve on the bypass line and shutting off the bypass either half or all the way. then all the coolant will go through the core vs some going through the bypass. im sure its unrelated, but the a/c quit working last summer. its a major surgry to change out the heater core, and it flows freely and doesnt leak so im thinking it should work as is, but im puzzeled as to why im not getting much heat out it. car has around 125K miles on it, water pump was changed around 3 years ago and i just put a new thermostat in, enegine seems to be at normal operating temperature. can coolant bypass hose be shut off and help with heat output?