During the close-up of Brandi taking off in the yellow Ferrari at the wedding, the sound is of a running sports car motor being put in gear and taking off, but in the close-up the steering wheel hits the lock just as she starts to turn it, so the key must be off and the motor can't actually be running.
Right after the wedding kiss, when Brandy drives off in anger, a close-up of her sitting in the yellow Ferrari as she is taking off, shows the steering wheel actually hit the key-off lock right as she starts to turn it. So the car she's sitting in for the shot isn't really running nor is the key on.
There are repeated references to an auto part off of a 1998 V10 engine. In 1998, there were no production cars sold in the United States that were available with a V10 engine.
Later in the movie, when Brandy is working under the hood of a car (ostensibly where the 1998 auto part came from) the car she is working on is a 1972 Chevrolet Nova.