[1971-Chevelle]

My friend's daughter has a 2012 Subaru Outback. She recently took a road trip and it started running badly and the AC wouldn't cool when she
was climbing going into Flagstaff. On the trip home, it worked fine, but just before she got to her mom's house, the dash lights went crazy and it
seems to have overheated.

The radiator was replaced and the coolant was filled properly after this incident (including new hoses and radiator cap). It ran fine for a few days.
They just headed to Texas for a vacation and the car did the same thing again (they were just over 200 miles from their destination). A shop that
looked at it claims that one of the hose clamps popped off (which I have never seen happen). They replaced two of the hose clamps with the worm
style clamps (which is not recommended on a radiator with plastic tanks).

Fast forward over 200 miles later - the car did the same thing again. At this point I am thinking that the first episode of overheating possibly caused
some engine damage that is leading to this stuff happening. There was no coolant mixing with oil, but that does not mean that there couldn't be exhaust
mixing with coolant.

It is at a shop in Texas right now, but they won't know anything until sometime tomorrow. I am just wondering if anyone here has any ideas on what might
be causing this issue. The engine in question is the naturally aspirated 2.5 liter.

 

[68Malibu]

I have seen thermostats intermittently stick closed. Happened to me on a Volkswagen I had decades ago. Had similar symptoms to what you describe. I replace thermostats now about every 50000 miles on my daily drivers.

 

[1971-Chevelle]

I did a little research and it seems that the Subaru 2.5 liter engines have had issues with cooling systems and blown head gaskets. I am hoping that it does not have that problem,
but I have a feeling that it will need a head gasket (or two).