I purchased a 2005 330i ZHP automatic with 240k miles a few months ago. It's been leaking coolant. 1 quart every 250 miles (2 weeks) of driving. Engine is not over heating. I saw the low coolant light twice and added coolant. I now add it every other day instead of waiting for the light. I did a pressure test today and there was no pressure. No smoke out of the exhaust. Replaced the cap. Looking at the temp sensor and it seems to not be leaking. Could it be a small head gasket leak? I will do the test soon. I'm debating if I should do the whole level 3 cooling refresh. A friend said it might not solve the leak issue so wait. Thoughts on next steps?