Jackie in Maine called the show and discussed lack of heat in her Taurus. She said she had the heater core “flushed.” I had a similar experience with my 96 Saturn wagon; a mechanic used an air compressor to force air through the heater core; he told me that “a big wad of snot” came out, and ever since I have plenty of heat!
i used plain radiator flush from local auto parts store. follow simple directions, and the small amount of stuff that was in the heater core that came out in a bucket amazed me that it was actually the problem. excellent heat now.