Hey, I've got a 2004 VW Lupo 1.0 MPI with 150000 km that I bought in 2018 and it's losing coolant when driving. In the city it's not much, the temperature is okay and it never really goes below Min. Refilling a little bit of coolant after several thousand kilometers is enough. But when I when I drive longer distances with high rpm (can't be avoided on a 49 hp car) the car loses the coolant much more quickly, once going well below minimum after a 1200 km drive. The temperature of the engine didn't go any higher than it normally does.
What could it be and can I keep driving like this without worrying?
Find the leak. Fix it. Problem solved.
You don’t wanna risk overheating your engine due to lack of coolant. Any white smoke from your exhaust?
No white smoke as far as I can tell. Looks like I have some work to do then. Thanks.
No worries & good luck.
Pressure-test the cooling system. If you're lucky it could be just a pinhole leak in a hose or a loose clamp.
Or, it could be a malfunctioning radiator cap.