If you have lost a sufficient amount of coolant this will stop the heater working because there will be no hot water in the heater rad.
If you mean engine coolant is getting into the car, the heater core is leaking coolant causing the coolant level to drop and that causes the engine to over heat.
Coolant leaking from the heater core.
chk coolant, chk coolant hose to turbo if it's a turbo. my hose was leaking causing overheating. My 2006 had a clogged heater core causing flow problems. Also the cooling fan is known to fail after 100k miles.
Check the coolant in the 96 Taurus. Check to insure that the thermostat is working properly, and that the water pump is working.
A leaking heater core will cause the engine to overheat because the coolant is leaking out.
the heater core, heater core hoses or heater control valve is leaking
Heater core / hose leaking.
If your talking about coolant leaking on the passenger floor then it means your heater core is leaking and needs to be replaced.
The heater core is leaking coolant.
Yes But: Breathing the anti-freeze fumes is not good for humans. Also running out of coolant and engine overheating will cause damage. If it's an emergency, bypass the heater core with a hose and clamps to route coolant back to engine.
Did you check the thermostat to make sure it is working? If it is and you have enough coolant, you might want to check for head gasket issue. You can rent a tester at Autozone. HTH
water pump