I've been playing the new build 41 (the latest update to be more accurate) and I've had a few bugs with cars:
1) Duped cars (look at the screenshot ). So I drove the police car by this spot, did some stuff then later drove back by this same spot and magic - the same car appeared like it was always there. It was the same car because it's condition was the same as mine's and it had the same loot inside (although the duped car had only things that I found at first in my original car, not the stuff that I loaded after).
2) Getting stuck in a car - I don't know how but when I got in my car, my vehicle UI disappeared (although if I pressed V, the circle vehicle UI could appear) and then if I tried to get out of the car - I couln't. Also wasn't being able to change sits, but was able to drive for some reason. Then when I quited the game, opened it again and loaded my save file - my character was at his first original spawn point without any loot that I got whatsoever. This character was the second in this game world, the first one died, but the keys to the car belonged to the 1st character and so as the loot.
3) Car vanishing. I parked my car just outside my house, went outside away from the house, quited the game, then loaded it again and got back to the house - my car vanished. After some time I found it on the road not so far away from my house. It's like it teleported away from the place where I left it.
I believe that those are all the same issues with vehicles, but I am not so sure.