2010 BMW 528i Base 6 Cyl 3.00L
How do I know if the thermostat is bad?
The car will warm up, the cooling fan does not come on, then the overflow expansion tank builds pressure and bursts. I have been through two expansion reservoirs already. I believe the cooling fan does not come on because it's thermostat related. I don't know where to go from here.
There are a couple of possibilities: