Taurus taking antifreeze........

I'm not sure if the Taurus used the same 3.0 V6 as the Windstar did, but if so, it's probably a headgasket. Pretty common issue, should it be the same engine. Do a compression/leakdown test and see if you can find the source, as well as a pressure test of the cooling system, if you have the equipment available.

You may still have a code stored, even though the CEL isn't illuminated, so pulling them may still be a good idea. I'm not sure what to make of the squeaking coming from the wires, aside from having a look around for anything that's loose in that area. Possible loose bellhousing bolt, maybe?

I know this thread is probably dead, but if you havn't gotten it fixed yet, sounds like you gotta bad cam sensor. By the squeeking noise you describe by wiring harness by the t-stat housing, and the driveability issues you are having. As far as the coolant usage; if you see coolant on the ground on the passanger side, you most likely have a front cover gasket issue. Also, if not fixed, i'd put a water pump on it too while you have it all apart, if you even have blades left on the water pump.