My wife has a 2011 Subaru Outback 3.6R that has been overheating intermittingly over the last year. It has around 165k miles and so far we have had the fans, fan module, and thermostat replaced. Two days after the thermostat was replaced, I had driven it for 2 hours mostly at highway speed. I was sitting in a parking lot and the AC got warm/hot and the flashing red overheat icon came on so I turned it off.
We purchased it used from a dealership and my father went with my wife and used one of the head gasket testers that you stick in the radiator but I’ve since read that head gasket failures don’t always present exhaust gas in the coolant. Does this sound like a head gasket failure or could it be something else? I feel like I’ve thrown money at this car since day 1 and don’t want throw any more if I don’t have to.