Errors in geography: During the auto race, the cars are supposed to be driving across the Hoover Dam from Nevada into Arizona. In reality, they are driving the wrong way across the dam, from Arizona into Nevada.
Continuity: When Rusty is dancing in a lavender bodysuit, she wears high heels until about 2/3 way through and then she is shown with lavender ballet slippers.
Continuity: When "The Coasters" first begin performing the song "The Climb," the close-up view shows none of them wearing glasses. When the camera zooms out to show the entire dance floor, the baritone/bass vocalist is wearing glasses.
Errors in geography: When Lucky and Rusty are taking off in a helicopter to view the Hoover Dam, the TWA terminal at New York City's JFK airport can clearly be seen in the background.
Revealing mistakes: In the dance/music scene on the "roulette wheel," Lucky is playing an electric guitar that is not plugged in.
Continuity: In the "What I Say" dance number white tape or something similar appears and disappears from Elvis' right hand fingers.
Continuity: The continuity of the big race is completely jumbled. For example the #19 Jaguar XK 120 is the first car to crash, yet it is plainly visible a few moments later bumping other cars off course. Lucky manages to weave his way through the whole pack to catch the race leader's Ferrari 250 GT and then they swap leads a few times. The Count's Ferrari blows a tire and crashes, then suddenly Lucky is once again passing the cars he just passed to catch the Count and take the lead.
Revealing mistakes: The Count's (very expensive) Ferrari 250 GT suddenly transforms into a Daimler 250 SP Dart right before it crashes.
Audio/visual unsynchronized: In the "What'd I Say" music scene, an electric piano can be heard very clearly on the soundtrack - yet only an acoustic concert piano is seen on film.