My 2014 VW Polo Vivo 1.4 has never bothered me when filling it with water every second day. It used to take sometimes two months without needing any water. Now I fill it every second day. What could be the problem?
It’s losing coolant. Is it running ok? Does it get hot? If the answer to those questions is ‘yes’ and ‘no’ then look for a leak from the radiator, radiator hoses, cooling system fittings on the engine. If the answers are ‘no’ and ‘yes’ then check for a leaking heard gasket.