How long is a crewed vehicle a creature
No, the vehicle stops being a creature at the end of your turn.


  702.121a Crew is an activated ability of Vehicle cards. “Crew N” means “Tap any number of untapped creatures you control with total power N
  or greater: This permanent becomes an artifact creature until end of
  turn.”


This is reflected in the reminder text most Vehicle cards have beside their Crew ability.

If you activate the Crew ability again on your opponent's turn, it will again become a creature and potentially be affected by the enchantment.

Source