Adaptive Cruise Control (ACC) techniques are now being put on the market as a safety and comfort feature. These ACC actually do not work at low speed, mostly because of limitations of the radar sensors being used. Using simple optical sensors, INRIA has demonstrated that it is possible to implement ACC in Stop&Go mode. Renault and other partners involved in the Urban Drive Control European project also implemented Stop&Go using radar and lidar sensors. This mode which could also include lateral control would be more useful to the driver faced with recurrent congestion. Detailed simulations which include the control algorithm of this ACC mode try to assess the impact of such systems on traffic flow.