"Open Source Car" which isn't

Unfortunately, some people don't realize that "Open Source" has a definition. They think it's a loosey-goosey term meaning "stuff that people like", more or less. So they apply it to anything which can be opened, like a door, or a box, or in this case, a car (english). Sorry, no. Unless they're actually publishing the design specifications, the blueprints, the CAD files for this car, it's not an Open Source car. And apparently Hilmar Simoncontacted them and no, they're not planning to give the design away to anybody.

To promote and protect open source software and communities...

For over 20 years the Open Source Initiative (OSI) has worked to raise awareness and adoption of open source software, and build bridges between open source communities of practice. As a global non-profit, the OSI champions software freedom in society through education, collaboration, and infrastructure, stewarding the Open Source Definition (OSD), and preventing abuse of the ideals and ethos inherent to the open source movement.

Open source software is made by many people and distributed under an OSD-compliant license which grants all the rights to use, study, change, and share the software in modified and unmodified form. Software freedom is essential to enabling community development of open source software.