Having the same problem with mine. Just got it back, noticed the coolant was low, topped it off, and it is still 'disappearing'. White residue on the inside of your exhaust tips, as well as on the electrodes of the spark plugs are a dead giveaway, but be sure to have it tested before your rip your engine apart. I'll be driving mine until I get some time/money saved.. If there is no oil leaking into the coolant or coolant leaking into the oil, and no overheating it won't force you to perform the repair immediately, it will just cause some performance issues... but the leak will worsen, so keep an eye on your coolant and engine oil for 'milkshake' or 'sludge'.