Vehicular network communication technology is currently attracting a considerable amount of attention. We consider a scenario in which vehicular communication nodes share the same spectrum resources and generate interference with other nodes. Compared with traditional interference-avoiding vehicular communications, this paper aims to increase the number of accessed communication links under the premise of satisfying the required QoS. In our research, communication nodes have opportunities to select relay nodes to both help improve their data transmissions and reduce their transmit power in order to decrease interference with other links while still satisfying their QoS requirements. Based on these objectives, we propose an innovative interference management method that considers link selection, power adaption, and communication mode selection simultaneously to maximize the number of communication links with the lowest power cost. Compared with traditional link-selection and power-adaption interference management schemes, the proposed scheme improves QoS satisfaction with high energy efficiency. Simulation results demonstrate both the efficiency and the effectiveness of the proposed scheme.