Lags & Invisible, Frozen & Stuck Sims --> Post here if you have the issue.

What town are you playing in
Does it start right away or do you play for a while
Have you tried the Overwatch mod. It clears cars that spawn like crazy

Have you made sure your video card driver is up to date. I thought mine was
and found out a new update just came out a week ago. Id check that

CC can mess you up but you say ou have not dl any. You can play it without
CC by ticking that box installed. I tried it when I had that problem bad
but it made no difference.

There are some very knowlegeable computer people on here that I hope will answer you
also.