Bingo!!
The only rule was 'I can't reveal the nationality' because once you'll knew it was from Canada, it was a matter of minutes.
The only clue was that I could not reveal the nationality: if it was from the USoA, what kind of clue was that?
I had to say it was not from Europe to avoid you to name all the cars made in those markets where the makers are not hundreds but what was left? Australia, Canada and Asia...given the fact that Africa and South America were out of the question. The look of the car was pretty American, so Canada was a valid guess and my replies were all in this direction.
I hope I did not waste your time and you enjoied the game like I did.
A well earned point for you Pal!