Various boosted cars (such as the RX-7) do not make the signature sounds of upgraded turbocharged cars throughout the film, such as the turbo spooling and the blow-off valve, until they "hit the nitrous." Nitrous does not change the car's sound.
When Han and Sean are in the RX-7 and talking, the engine tone shifts at least 7 times, as if the car has 7 or 8 gears, most of which have the same ratio and thus engine tone. Sean's hands remain on the steering wheel throughout the drive, yet the shifts still occur. In addition, they do not have the pitch a manual car would have (revs dropping from engaging the clutch, then shifting into the next gear). The two transmission choices for the car were a 4 speed automatic and a 5 speed manual. This is a recurring mistake in the Fast and Furious movie line.
When Sean and Han escape Han's shop, they drift while trying to evade D.K. and his crew. They would have much better chance if they drove in a clean line, instead of drifting, which makes the car much slower.
In the beginning of the movie, when the baseball is thrown at Sean's car, it goes past him and lands on the passenger floorboard. In the next shot, the ball falls to the ground, with glass landing behind the rear tire, as if the ball had been thrown from inside the car.
When Sean is first given the red Mitsubishi Lancer Evolution IX, his numerous collisions while practicing around the harbor tear off the rear spoiler. When he starts practicing on the hills, the EVO has no spoiler, but when he first drives uphill, the spoiler is on the trunk. Subsequent shots show the EVO without the spoiler.
During the first race between the Monte Carlo and Viper, the starter pulls off her bra and throws it in the air. It lands about 10 feet in front of the two cars. Both drivers shift gears, accelerate for a few seconds, then drive past the bra, which is now 100 to 200 feet from where it landed.
Shortly after Twinkie's Volkswagen Touran "Hulkmobile" minivan is introduced, Shawn and Twinkie drive off. In the next scene, when the Touran enters the car park, a set of tires appear on its roof. In a deleted scene, Reiko and Earl steal tires from a gas station.
When Sean and Neela eat Japanese food on their first date, Neela puts the chopsticks in the box. When the camera focuses on Sean with Neela in the foreground, she is holding the chopsticks again. When the camera cuts back to Neela, the chopsticks are back in the box.
In the final moments of the last race between D.K. and Sean, the Fairlady Z sideswipes the Mustang and loses its passenger side light. D.K. drives up the side of the hill, where small trees and shrubs knock out the driver's headlight. In subsequent scenes, the driver's headlight is attached and working.
When Sean first drives with Han to get money from the "Paw" to collect money, the RX7 they drive in originally shows it being a "left hand drive" car.
When he is thrown out of the building and then they decide to drive, the car then becomes a right hand drive and seems to be the case through out the rest of the movie.
In the beginning, when a baseball is thrown through the back window of Sean's car. In the next shot, from a higher viewpoint, the car stops, and the window is intact. In the next shot, it is broken again.
When Sean is walking past the cars before speaking with Neela in the parking garage, you see a golden Toyota Supra behind him on his right. He then looks to the left, and it shows a close-up of the girl sitting on the Supra, which is to the right of the camera. Additionally, in the next shot, he looks left, and the Toyota Supra is well behind him.
During the first race, in America, the Viper drives through a shadow of the house before Sean takes the shortcut between the houses. When the camera moves out and shows both cars from above, the shadow is gone.
When Han drives donuts around the two women in the Mitsubishi, his car stops such that if the women drive forward, they'll hit the rear/side of his RX-7, but in the next shot, his car is parallel to the women's.
When Sean, Neela, D.K., and Sean's dad meet after Han's accident, the camera is near the headlight of the Fairlady Z. Light circles appear for a few seconds, in the bottom right of the screen, where the lens of the camera caused distortion from the headlights.
If Twinkie was a military brat, his license plate would have a Japanese symbol that looks like a "Y" on the left side. Military members and their families with cars in Japan are required to have "Y" plates.
Sean's father is credited as "Major Boswell". In a scene where he is in Naval uniform, his shoulder board clearly displays the two full stripes of a full Lieutenant, and the collar insignia, while improperly gold, also has the two bars of a Lieutenant. The rank of full Lieutenant in the Navy is O-3. Major is used in the Marine Corps, Army, and Air Force, but not the Navy. It's O-4; the Naval equivalent is Lieutenant Commander. Major is denoted by a gold oak leaf cluster, not twin silver bars. A Lieutenant Commander in the Navy also carries the gold oak leaf cluster on his collar, and the shoulder board carries two full strips and one half strip between.
When the baseball goes through Sean's car window, the driver puts the car in park. (The shifter could be mounted on the steering wheel, but it's not clear). The car has a clutch during the race, yet the floor shifter is semi-automatic.