YORKIE QUES. IM SOOO CURIOUS WHY>>>?

ok so i have a yorkie whos 2yo. i want to start bringing him on trips in the car with me so i tried bringing him on a short few blocks drive with the AC on and he sits still for the most part but pants like crazy....will he eer get used to the car?...ALSO, why does he try to dig his FAVE toy in the dirt? THANKS!!!!!