My friend owns a VW Golf Mk4 1.6 SR year 1998. Recently he is having issues with the coolant fluid being consumed up really fast, approximately 1.5 liters in just two to three days.
The first thing that came to mind was checking for a leak. Both when the car is turned on and turned off there is no sign of a leak, all the hoses are looking okay.
The car was even looked by a mechanic and even he does not have a clue of what could be the problem.
Is is somehow possible that this fluid evaporates somewhere, or what else could be the issue?