When fuel burns, the main byproducts of combustion are H2O (water) and CO2 (carbon dioxide). It is normal for water vapor in the exhaust to become liquid water. Coolant in the exhaust would have a very different sweet smell and lots of visible smoke. If you were getting coolant in the cylinders, you would also be building pressure in the cooling system forcing coolant back in the coolant reservoir and eventually overheating. So big question is what is the level of coolant in the reservoir?