Vw Golf Leaking Coolant. 20180417 The airlock is a really common and known issue air not expelled from system at the factory leaches out over time causing coolant level to drop so it can appear to be a leak but in this case its not. Its been looked at and no visible leaks were seen it has been pressure tested and all came back fine.
Also since you already have what looks like clean green coolant in there dont mix it with pink VW coolant. 20130913 The Golf 5 has a common habit of a leaking radiator at the lower corners often on the cars left viewed from behind. Ring under the thermostat had perished.
If nothing there it would be a fair bet that it is the cooling flange.
Remove the intercooler and pressure test it underwater. 20201221 Volkswagen Golf owners have reported 1 problem related to coolant leaking under the engine and engine cooling category. Unfortunately you are out of the three year bumper to bumper and coolant leak would not be considered covered under powertrain. If coolant from your VW is leaking from the water pump the internal bearing and seals are most likely weak and there will be a trail of coolant from the pump region down towards the engineIf there is steam blowing from the engine the coolant leak.
