 Burning Water
Its possible to burn small amounts of water (your exhaust will smell like coolant), but this sounds like a large quantity you're running through.
Check the oil (should be the first thing) and look for signs of water in the oil.
Assuming you have checked all the usual suspects for external leaks while the car is sitting still (no pools under the car I assume), its possible you have a high pressure leak, ie, one that occurs only when the car is hot and running. Take the car out and get it up to full operating temp and then bring it home and park it running. Get a flashlight and eyeball around the radiator, hoses, waterpump and heads to look for wet streaks or a fine mist of water shooting out, or steam.
If you see corrosion on the outside of the radiator, or trails of white or greenish corrosion around its base, or similar signs elsewhere in the cooling system (hoses, clamps, 'stat, water pump, heads, heater hoses, heater core, etc), there's the suspect, even if you don't see water dripping.
Check the carpet up under the dash - if its damp, you have a heater problem.
__________________ tripleblack
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