This paper presents ComFASE, a communication fault and attack simulation engine. ComFASE is used to identify and evaluate potentially dangerous behaviours of interconnected automated vehicles in the presence of faults and attacks in wireless vehicular networks. ComFASE is built on top of OMNET++ (a network simulator) and integrates SUMO (a traffic simulator) and Veins (a vehicular network simulator). The tool is flexible in modelling different types of faults and attacks and can be effectively used to study the interplay between safety and cybersecurity attributes by injecting cybersecurity attacks and evaluating their safety implications. To demonstrate the tool, we present results from a series of simulation experiments, where we injected delay and denial-of-service attacks on wireless messages exchanged between vehicles in a platooning application. The results show how different variants of attacks influence the platooning system in terms of collision incidents.