First, you have to FIND the leak.
It can be a hose, the water pump, the radiator, head gasket, radiator cap... let me know what you find, and if you can't figure out what to do, we'll talk.
How to fix this depends on where specifically it is leaking from.
Look for a leaking hose, water pump, or raditor find the leak and fix it.
you fix the leak
First check the coolant level, a coolant leak would cause a heater to stop working- assuming you mean the blower is blowing but it isn't hot. A stuck thermostat will also cause you problems with your heat.
Fix the leak, and fill the coolant.
Just because there is a leak doesn't mean it will overheat instantly, but if you do not keep adding coolant or fix the leak you will have engine problem
Fix the coolant leak.Chances are the water pump has a problem. They were known for having a leak and with no coolant you have no cooling.But you may have a coolant leak elsewhere also. Your cooling system will need to be checked out.
probably just replace the coolant sensor
A leak in a coolant system can usually be fixed by replacing a hose. If the leak is at the end of the hose, a new clamp might be necessary. If the radiator is leaking, the radiator might need to be replaced.
Yes, I had to do the same on my 1.9L DOHC 1992 Saturn, I had a small leak in my radiator and can tell you this works well for a while but is not the ultimate fix, my leak keept getting bigger and bigger until y finally had to spend some money and put a new radiator
Did you ever have a coolant leak?
Coolant leak, possible heater core. Suggest to have it pressure tested to find leak.