The traffic lights need a set timer. When playing, I'm seeing red lights staying red. green lights staying green, and not changing, mainly being on the outer edges of the city, which is causing these large traffic jams. Maybe the game already has a timer, I don't know, but from what I've seen, only certain traffic lights work properly. I feel a 20 - 30 second timer would work really will, it'd keep traffic flowing smoothly, and keep the feel of new york. You'd still have those long lines of traffic without gridlock.