I downloaded your STL file and fixed some or the cells (triple bounds, collapsed cells, and so on…). The quality of the STL could certainly be improved, as there are a lot of “needle” cells, and the size and shape of cells is far from homogeneous.
Another thing I did was split the car into different elements: body, wheels, rims, and rearview mirror. More could be defined, which would be useful in order to assign different surface refinements, but for the nonce this should suffice. It’s important to bear in mind that with just a single surface, the layer addition won’t work, thus you won’t get any boundary layer cells with your STL.
Furthermore, I also added MRF zones for the left rims. When you create a symmetry case, with the left side of the STL you can have MRF, and with the right one you can do without it.
You can see the resulting mesh (TeslaModel3 mesh) in my dashboard: