heating and cooling

I have taken my LaCrosse in twice under warranty for cooling and heating issues. The fix was the service guy giving me a printout of how it works. This tells me the service department does not know how to fix it. I have now figured out on my own it is a faulty ambient temperature sensor...

Got a secret-style coolant leak. It's behind the glove box, and what I'm guessing is the heater core. It's been secret because I haven't been able to locate it for months. Overflow reservoir keeps going down almost to empty but through pressure testing a couple of times and checking what I...