I did a ~35-minute test this morning, and got the same kind of results rybolt graphed. I set the Bolt's thermostat to 74, fan on Auto. Temp in the front seats rose to 86 degrees. I would not be surprised if the car got to 89 degrees as rybolt's did, if I were to continue running the climate control at 74 for a full hour, as he did. Twelve degrees and climbing is already a big enough malfunction to make the Bolt's auto temperature control worthless.
I've seen a handful of comments from various owners regarding this issue. Not enough data to say for sure, but sounds like this could be a problem for
a) all Bolts,
b) a significant number of Bolts, or perhaps
c) most or all Bolts built before a certain date (mine was December).
So, here's my question: Is there anyone who can leave their Bolt set to 74 degrees for a half hour and remain comfortable?