Okay, looking at her receipt, they bypassed the heater core. Putting heater core replacement 99 sable in the magic Google machine gave me two videos telling me to saw off this piece of metal or that piece of plastic and then this .pdf. Please skip to page five:
http://airsept.com/Articles/RecycleG...cs_SR03.03.pdf
What do you guys think?
Someone else suggested reverse-flushing the heater core. I liked this write-up. It is the same for a Ford as for a Cadillac, right?
Heater Core Back Flush Instructions & Pics