Many system-development projects today are mainly driven by the complexity of their software interacting with sensors or actuators in an embedded context. Autonomous vehicle development is a domain where it seems inevitably necessary to apply modern development techniques to cope with complexity, increase development efficiency, and ensure appropriate quality. Furthermore, changes that are triggered by customers or inventions of competitors, as well as bugs, enforce a comprehensible, if necessary, yet agile development process with stringent quality management. In this paper, we describe the agile efficiency- and quality-focused change management mainly based on scenario-driven regression simulation used in the CarOLO project for the development of an autonomously driving vehicle to compete in the 2007 Defense Advanced Research Projects Agency (DARPA) Urban Challenge program. The main contribution is the demonstration of the modern software engineering techniques' applicability to develop distributed embedded systems.