New to forum but wanted to share this info as I believe it will save others time and money and was relatively easy spare the crap that happened.
Let me start, first off car has 235K miles and going strong but I lost heat a month or two ago when all of sudden I started seeing coolant come rushing out of the engine, saw from underneath that my head gasket was leaking quite nicely so I was about 60 miles from home but 1 mile from autozone.
Put in bottle of bars leaks head gasket repair and a gallon of 50/50 prestone and after about 2 minutes of the engine running no more leak
but right away noticed no more heat too
So it was time to take a look at blowing out the heater core to see if it was clogged etc.
Found a great link from the 1A Auto guy, this guy is the best.
and I followed this to a tee.
My problem was first off mine was again, 235K miles into it and back about 5 years ago I plopped JB Weld cold weld around a bend in the heater hose assembly as it was rusting and leaking so for $3 I fixed that without having to take out the heater hose assembly.
Well after doing this step by step, when it came to getting the hoses off the heater core metal bibs, one of the damn bibs broke off on me, guess what, now time to replace the heater core.
All I read about that was what a nightmare and how much time/labor costs etc so I went at it my self after reading this I found.
1996 - 2005 Ford Taurus Heater Core Replacement
One thing they did not tell you here but I read on another PDF I found was that by removing the dashboard 7 bolts (really not a big deal at all, I am a computer guy and If I can do, anyone can really ). I got under the glove box with my shoulder and was able to just lift the dash out about 2 inches and up about 2 inches just enough to squeak the heater core out.
Because I had the heater hose assembly off, I just went in through the engine and pushed the remaining bib through the firewall and it poked out under the dash about 3 inches, enough to grab it.
Again, had to change the heater core now so luckily autozone had it for $60 bucks.
Now reversed the shoulder push to get the heater core back into place, put back the dash, closed the cover, put back the metal slider and the white box with the electrical plug and the inside was done.
Back to following the nice gentleman from 1A Auto and reattached all of the hoses and the two bolts, refilled the antifreeze and viola HEAT!!!!!
Now all of that said it really took me about 1-2 hours to get the heater hose assembly out, again the hoses were really stuck and getting underneath the car up on blocks with a skinny hand and a bent nose pliers to get those damn clamps off was the real pain and then getting the clamps back on but lesson learned.
All in all $60 for heater core, $45 for heater hose assembly and about 3 good hours of labor, it was all done.
Hope this helps someone out there.