I have a 2000 ford taurus that is blowing cold air...no heat at all...we flushed the system,replaced the heater core,replaced the thermostat and still no heat....please help.

Did you check the bled doors inside the cabin under the dash? They could be defective Check the fuses for them first...

Were the air pockets bled out while filling it up?

What's up Rowefast, happy Thanksgiving...

Same to you man! My garage now has heat for the winter...

That is great news, nothing like a heated Mam Cave..

Once the vehicle reaches operating temperature feel the heater hoses going into and out from heater core do they feel like they are the same temperature. If one is warm and one is lukewarm heater core is partially clogged. If they both feel warm suggest following joemoms advice.

Air bound, air pockets will cause one heater hose to be cool, the other would be warm.

Brup the system to get the air out...

It would be air if the top and bottom radiator hoses where different temperatures.