Import and export preposition usage

Consider the following phrases:

1. The car was imported from Detroit.


2. The car was exported from Detroit.


3. The car was imported to Detroit.


4. The car was exported to Detroit.

Are these all semantically correct? Do (1 & 2) and (3 & 4) both mean the same thing?

When using import/export, I often wonder whether or not there are subtle differences in the meanings between the two aforementioned pairs of sentences, and whether or not they are all accepted usage combinations of import/export and to/from. Instinctively, I think that one should always say 'import from' and 'export to' (1 & 4), and avoid using the structure of (2 & 3), but perhaps this is misguided.

Any clarification or scholarly references to the accepted preposition usage with import/export would be very helpful.