cant think of this film

[Kris]

its something about this indian girl and her brother who get with another boy or something and are chased by bad guys on an island.
i remember one part in the begining her brother puts a potato in the exhast pipe of one of the "bad guys" car
and throughout the movie the sister has like random indian spiritual things happen to her or something
one point in the movie on the island the sister also finds a random hidden cave
i think it is from the 80s or 90s
the title i think has the world island in it...but i really cant remember