When Clarke and Danielle abandon his dad's car there is a group of trees right behind the vehicle alongside the road. When the police stop to check it out later, the trees are no longer there.
The movie is supposedly set in 1987, but the cash the lead character is shown stealing in the trailer ($10 and $5 bills) is clearly modern U.S. currency featuring enhanced security features like large numbers and different colored inks - not bills from the 1980s.
The acoustic cover of "Your Love" by The Outfield playing during Joel's strip tease for Clarke wasn't recorded until 1992, five years after the time the film depicts.
On the morning that Danielle and Clarke leave for California, Danielle wakes Clarke up and he asks her where she wants to eat breakfast then says he thinks "Sambo's" takes credit cards. Sambo's closed the last of its locations (excluding the original) in 1982, five years before the film was supposed to take place.
When Danielle first arrives at her Dad's house she is wearing designer jeans which were not popular in 1987.