Jake has no problems in the car but I have a suggestion...
Try going in and out of the car with your dog when you dont plan on going out.
Run the AC in the car for a few mins before getting in (as you mentioned that the car was really hot when this behavior started) and then just have a romp about the back seat with your doggie.
Just a 1 min game and then take him out again.
Keep on doing this ... every hour or so.
Might help ... Might traumatize him for live
