Etios Coolant Loss

That sounds familiar. I had the same thing with my 2016 Opel Astra: coolant disappearing, check engine light, the works. I'm no expert, but have you checked the coolant reservoir cap to see if it's sealing properly? What about the cooling fan – is it working right? Mine turned out to be a hairline crack in the engine block, which you could only see under pressure. Could it be a coolant leak?

Thanks. The coolant reservoir cap looks okay, and the cooling fan seems to be working fine. A hairline crack in the engine block sounds bad. Is there any way to find a crack like that without taking the whole engine apart? Maybe a cooling system pressure test?

Yeah, a pressure test should show a hairline crack because the pressure will drop too fast. It could be something small, like a bad hose, but that crack is possible. I'd take it to a workshop. They can find out where the coolant is going.

Thanks for the advice. I booked a pressure test with a mechanic to check for a hairline crack or other leaks. I went to the workshop, and they replaced the water pump and the thermostat. The coolant level is fine now. The total cost was 52€.