Normal Engine Temperature but Coolant finishes daily, No leakeages traced

It is very possible the culprit is the radiator cap.

It is likely the coolant is not reaching operating temperature, please verify the engine thermostat is working.

Look in the radiator in the morning when car is cold take off the cap if it is full then look at the reservoir and make sure you see to lines on it one you fill to when cols the other you fill to when how it will say hot and cold fill lines fill yo cold when it is cold then next day check and see when cold if it is at the same mark

this coolant level indicator add coolant S.W off and on . check coolant leakage from radiator there is thermo S.W sender little leakage re tigh . keep coolant on level .

first thing to check is your coolant level. a lot of fluctuation will occur if the coolant level is low. if it is, be sure to find the leak to avoid engine damage. other causes can be plugged radiator, faulty thermostat, etc. but start with the coolant level.

Engine showing hot but heater not putting out heat is a sure sign you are low on coolant! Not knowing the percent of antifreeze, I couldn't give a absolute answer but I know this... Go buy one of those coolant testers at a auto supply, test a sample of the remaining coolant. If it shows you were not protected to the very cold temperatures you can get there in Toronto, then you may be in trouble, my friend. The only way to tell for sure is to first get the car inside somewhere warm and let it thaw good. While waiting, visually check the engine, radiator, and hoses all over for signs of freezing, like holes, cracks, popped freeze plugs, etc. If you find something that can be fixed, fix it. The goal is to test for leaks. Fill car with plain water and if it's not leaking any more, run it up to temperature and see what happens. If it acts OK, at that point drain all water, add proper amount of coolant, and retest using the coolant tester tool I mentioned earlier. One thing I forgot to mention when filling vw engines with coolant. Don't know about the newer Golfs but the older rabbits had a bad problem trapping air in the head when filling coolant because the reserve tank was positioned too low. If yours is higher than the top of the engine, your OK but if not, the solution is to take loose the top radiator hose at the radiator and lift it up higher than engine. Continuing to hold it high, you then pour coolant in the hose until it comes out the radiator then quickly re-attach the hose and re-tighten it. Now, back to cooling solutions.... if you are still having same problem, check that your water pump belt is tight. When the engine just gets up to temperature, check that the electric fan is coming on. After engine is too warm to leave your hand on it, feel the top hose to see if warm coolant is flowing. If not, you may need to pull the thermostat, heat it up in a pan of water to at least the temperature stamped on the thermostat, and check that it physically opens all the way. (Use a meat or candy thermometer to check the water temp). That's about it my friend. Good luck and let me know how it goes?

Could be a small hole or a crack in the housing that the sensor goes in. Also check the housing gasket.

Is the heater nice and hot when the needle shows low temp? If the cooling fans turn on and the heater is hot, that leads me to believe the coolant temperature sensor is bad. You should try replacing that sensor. They are only $6 usd here. As long as your check engine light is not on and your fans are running, this will not hurt your car... but this is something you should fix soon if you can. Make sure the engine is cold when you replace the sensor

It's actually on the Driver side towards the firewall/windshield. The reservoir looks like a globe. Make sure your engine is cool and remove cap, fill to recommended level (see the lines on the outside of the sphere, should be about half-way).

Found hints on VolkswagenTalk.com suggesting to check inside engine oil cap. If you find foam (some call it ice-cream) Cylinder head gasket is blown. Went checked, and actually found ice-cream on it. Credit to Hillbill, Man you Rock!

I am now doing pressure test, but no wapping has been detected..problem was just in its early stages. on my way to get a metal gasket, and replace. Cheerz!