I got my 14 TG back from the shop yesterday. They said they think the coolant didn't actually leak out or vaporize while I was running it. The working theory is that the system had an air pocket because they did not bleed it properly the last time they replaced the thermostat housing. They said they drained the system, replaced the fluid and ran it for a while. (A half a fuel tank for a while) I understand what they're saying and really hope that's all it was. Does this problem sound familiar to anyone?