LOL!! I live in an apartment, third floor. No garage in sight. But if I have more than I can carry upstairs on one trip, I leave the non-perishables in the car for a day or two until I go back out again.
I used to live in a 3rd floor condo with NO elevator! Thankfully last June we moved into a one floor house.
So yes, leaving stuff in car for some hours will kill the virus.