Try to find a place where you can walk the pup that you are a reasonable distance from the cars going by, rather than right on the street. Just think how big and scarey a car is to a small pup. I walk my guys in a park that has a walkway about 20-30 feet from the road; that way they get comfortable with the idea - can see and hear the cars whizzing by but the cars aren't so close that they panic. Eventually they figure out that the cars aren't going to climb through the ditch to come get us, lol. A little fear of cars can be a good thing, incidentally. Stay outta the road, little doggies.