Besides the possibility of a faulty sensor or gauge (other instruments are faulty), old coolant could have been an issue.


Issue: Gauge only went into "Normal" range during hotter days, in traffic. Now doesn't indicate anything at all.


Cause: Thermostat was, yes, broken! There are 2 metal tabs which hold the upper and lower disc together, which are housing the betel spring inside.


One of them was simply broken, looked like a clean cut.


A new thermostat, coolant flush and refill (mine looked like being 15 years old) everything is fine now, gauge reads the way it should, and yes, I do have hot air now coming out of the vents.


Greetings!