Vehicle Won't Display TITLE tag after using TAG - TAG

You can compare a track with the TITLE filled by Convert Tag -> Tag and %_filename% with another track where you filled the TITLE content manually.

Press Alt+T on the two tracks and compare the content.
If you like, you can show us a screenshot of both metadata overviews.

BTW: Have you entered exactly the same content manually?
Or was it much shorter, or did it not contain any special characters?

I assume this is your Toyota car?