This started in the summer with driving, slowing down and then the car would stall. I would have to completely shut it down for a minute, in trafic. I was told it was due to high temperatures outside.

The battery has been replaced twice and the dealership just said use higer octane, which we already used. They also said that their is basically no fix! I'm regretting buying this vehicle. Plenty can run in hot temperatures.
Yesterday, it was 60 degrees outside and it wouldn't even turn over. This car isn't even three years old.