Trivia: When Crazy Dave is putting the chain on Herbie at his yard, Herbie squirts oil all over his foot. This is a reference to the 1968 film "The Love Bug", in which Herbie did exactly the same thing to Thorndyke (David Tomlinson).
Trivia: In the first test screenings of this movie, parents believed the Lindsay Lohan was too 'busty' for a Disney movie. Disney then went back and digitally raised her neckline, and decreased the size of her breasts by two cups.
Answer: It is explained in the 1997 version of "the love bug". When a scientist was building Herbie, a picture of the scientist's deceased wife who he loved very much fell into the container of molten metal. This accidental action caused Herbie to have love for any owner he has.