Three cars in my house leak antifreeze, all three around 100k miles. car1.leaks slowly, warms a little 98 lumina. Dad say water pump. car2. leaks alot, warms really nice 99 lumina. car3. leaks alot, been crashed twice, only heats when antifreeze there 97 taurus.

in my opinion the #1 most common place is from the oil filter housing. Stand at the front of the engine bay, look at the right side of the engine block under the intake manifold. If the block is oily, wet, then that's the culprit. There's a $5 oil seal that dries out and can end up causing oil drops on your driveway. The labor for this repair can be several hundred bucks. it takes about 3-4 hours. Other common areas are the valve cover gasket in cars over 100K miles. If you smell oil burning inside the car, when you start it up in the morning, it's likely leaking here and getting on the exhaust manifold where it burns off..
Next place to look is the high pressure hose form the vanos to the oil filter housing. It's a 8" hose with banjo fittings. Over the years they can start to leak a little. Lastly the oil pan gasket can start to leak on cars with high mileage. My 98 323is has had all four over the years. It has almost 200K on it. I've done the oil filter housing gasket and some day will do the rest
The oil filter gasket is the one that leaks the most. It's not hard to do yourself if you are mechanically. There might be youtube videos to help. Good luck.

follow your upper radiator hose from the radiator back to the engine. At that point remove the hose and replace it. Put it back together , fill up the antifreeze and you are ready to go.

The water pumps tend to slowly leak on these, it may be leaking slowly, usually it leaves a coolant residue on the front of the engine and near the front of the oil pan. It is temp sensitive, usually leaks cold and stops leaking when warm

Is the carpet wet on the passenger side? Sound like you got a heater core leaking.Have fun replacing it.

Make sure the motor is cool you can drain down some antifreeze from radiator or slowly remove top radiator hose remove the bolts holding the housing remove housing remove thermostat clean block and housing install new o-ring or gasket which ever it has install new thermostat bolts hose re-fill radiator start let warm up check for leaks and add anti-freeze if needed.

It sounds like your water pump is shot. The small antifreeze leak is the coolant probably coming from the weep hole on the water pump. If you ran the car while the temperature was up, you may have to watch the head gaskets from now on as they may be shot. Water pumps wear out around 100k to 150k miles usually.

You didn't mention how many miles are on the vehicle but your symptom points to a water pump with failed seals. They don't often fail at less than 100K but they can.

There is a small hole at the bottom of the pump housing that allows coolant to leak out if the seals fail to prevent the coolant from ending up inside the engine and damaging it.

Let me guess - you have roughly 100k give or take 20k miles on your car, I had the same exact problem, you need to replace your intake, it costs roughly $150 for everything and it takes about 4-6 hours, common hand tools and some patience - the stove pipe coming from your EGR slowly deteriorated the coolant passage in the intake directly behind the throttle body from the excessive heat as well as the acidic properties of the dexcool antifreeze - The Dorman intake manifold has a redesighned stove pipe and works great and as well as flushing out the Dexcool and using the old fasioned green antifreeze - Don not be fooled into it being the Head gasket, the 3800 engine is bullet proof and is not know for head gasket failure - once you have the intake off you will see antifreeze in your intake. - Also a word of advice, while you are in there replace your lower intake gasket as well, you will be thankful you did, Auto Zone carries everthing you need as well as the repair guide available online.

blown head gasket. the coolant gotten into the oil.

how often does the warning comes on doing the week or in two weeks? if it was a one time thing or this takes place every 3-5 months i wouldn't worry about it. i will make sure that the radiator cap is on tight. you said that all hose seem to be in good condition i would check the radiator where the cooling fan covers the fins and the water pump because it has a warn hole at the base that will seep out antifreeze when the inside seals are going bad these will cause the smell also.