1998 Ford Taurus no heat

Okay do the following:
-Make sure your level of coolant is good
-Make sure there's no air in your cooling system. Bleed it.
-Is your engine taking a long time to warm up? You could have a thermostat stuck open. Replace it. If you never replaced the thermostat I would go ahead and do it now regardless if it's the culprit for your heating problem or not. It is a cheap fix ($5).
-with car idling at normal operating temperature and heat set on high, feel both heater hoses (smaller hoses connected to your heater core inlet and outlet on the firewall); they should both feel very hot. If one is cold or just lukewarm your heater core is probably clogged. Flush it or replace it.

If you've never serviced the cooling system, it is something I would advise you to do as well.

Come back if you need more help, or if everything I mentioned check out ok.

These are the steps
WARNING: NEVER REMOVE THE PRESSURE RELIEF CAP UNDER ANY CONDITIONS WHILE THE ENGINE IS OPERATING. FAILURE TO FOLLOW THESE INSTRUCTIONS COULD RESULT IN DAMAGE TO THE COOLING SYSTEM OR ENGINE AND/OR PERSONAL INJURY. TO AVOID HAVING SCALDING HOT COOLANT OR STEAM BLOW OUT OF THE COOLING SYSTEM OR DEGAS BOTTLE, USE EXTREME CARE WHEN REMOVING THE PRESSURE RELIEF CAP FROM A HOT COOLING SYSTEM OR DEGAS BOTTLE. WAIT UNTIL THE ENGINE HAS COOLED, THEN WRAP A THICK CLOTH AROUND THE PRESSURE RELIEF CAP AND TURN IT SLOWLY UNTIL PRESSURE BEGINS TO RELEASE. STEP BACK WHILE THE PRESSURE IS RELEASED FROM THE COOLING SYSTEM. WHEN CERTAIN ALL PRESSURE HAS BEEN RELEASED, PRESS DOWN ON THE PRESSURE CAP (STILL WITH A CLOTH), TURN AND REMOVE PRESSURE RELIEF CAP.
Engine cool
lower the coolant level
Locate the two hoses running to the heater core
disconnect them at the engine side leaving hoses connected to heater core throw the firewall
use garden water hose and compressed air if possible
run the water and follow by air throw one side and out the other and vice versa
do that two to three times watching what leaving the heater core you are looking for the good flow and clear water to run throw
good luck
let me know