Continuity mistake: When Christine is fixing herself after the guys smashed her up, her front end is shown to be perfectly straight for its entire width and the hood is missing. Near the end of the scene, the front end is shown crushed and unfolds again, and the hood appears from nowhere.
Revealing mistake: In the scene when Christine smashed repeatedly into the silver Camaro at the gas station, there is no motor in the Camaro. The hood of the Camaro gets knocked off the hinges and is twisted sideways on the car. As Christine is in reverse and dragging the Camaro along you can see down through the hood that the engine compartment is empty. Minus a transmission also, I believe. (01:15:30)
Plot hole: George Lebay says that his brother died "6 weeks ago" inside Christine and that's why he's selling it. Later that evening after Arnie leaves his house and goes to Darnell's, Will Darnell says he "knew a guy who owned a car like that" and "the bastard killed himself in it." If it's only been 6 weeks since his death, shouldn't Darnell have recognized the car? It's not like there were lots of red Plymouth Furies (custom order color) running around the small town, let alone the USA, even in 1978. (Also considering how production even had a hard time finding them for the movie).
Continuity mistake: At the the end of the film, Dennis uses the Caterpillar tractor to ram Christine. He also immobilizes the car by dropping the teeth of the loading bucket into the roof. Then we see close-ups of the car repairing itself completely. The next shot, just before the tractor starts to crush the car, shows the car in its previous smashed-up condition again. (01:44:15)
Continuity mistake: When Buddy stops his Camaro in front of the fuel station's service bay, the car is oriented at about a 45% angle to the facade of the building. But as he and the others step out, the car is parallel to the facade. This is even more obvious just as Christine crashes into the Camaro for the first time. (01:15:05)
Visible crew/equipment: When Christine smashes into the little white car inside Darnell's garage, she gets hooked to the car. Christine backs up trying to disconnect herself from the white car. When the white car finally is released, the momentum of the maneuver sends the white car skidding into other cars. Look carefully and you will see the casters mounted underneath the white car allowing it to easily skid along the floor. (01:37:30)
Continuity mistake: When Christine is crushed and dropped from the junkyard crane, the side facing Dennis, Leigh and Junkins shows a steel wheel very prominently. As they talk, they are looking right at it, and when the shot returns to the cube, the wheel is gone, replaced by Christine's mangled grillwork and front bumper- as if the cube has spun 180 degrees. The viewing angle is unchanged, evidenced by the crane's tread belts and the area in the background, and if the cube were 'morphing', the 3 characters would have seen it and reacted. (01:45:10)
Continuity mistake: At the gas station that explodes, a car is lifted high in the left service bay, but is down on the floor when the building explodes. To try and fix this continuity error, a quick close-up shows the controls for the right bay's lift as Christine shoves the Camaro inside the right bay, smashing those controls. This should have no effect on the left lift (each lift is completely independent for safety), yet two quick close-ups (of the blonde guy, then his feet) show the car on the left is now coming down. But long before it could have traveled all the way down, the next shot is from outside as the building explodes with the car firmly on the floor. (01:15:55)
Continuity mistake: When the gas station explodes, one closer shot shows the far right end of the station where the tow truck is parked next to two fuel pumps. Behind the truck, the grounds erupts with a huge explosion. The next shot shows the entire station from further away, and at the right is the truck and two pumps with no fireball rising behind them, yet there should be. (01:16:50)
Factual error: When Christine is about to crush Moochie you see the car is a few inches wider than the entrance to the loading dock. Even a small box truck that you can rent is 7'3" wide so that opening would have to be wider than that for the truck to back in. A 1958 Plymouth Fury is only 6'6" wide. Christine would have had plenty of room to just drive in and crush Moochie. (01:45:45)
Factual error: There are a few scenes in the movie which show Christine locking her doors and we see that she has common lock "buttons" on the inside door panels. This is incorrect - 1958 Plymouths are not equipped with buttons. To lock the door, the door handle has to be rotated counter-clockwise. (00:48:15)
Continuity mistake: When Christine is about to push the Camaro sideways into the service bay, an interior shot looking at Trelawney in the bay, screaming, shows that the Camaro is already moving sideways before it is hit by Christine, yet the next exterior shows it isn't moving yet. (01:15:55)
Continuity mistake: When Leigh is choking inside the car at the drive-in, the speaker hanging on the driver-side door glass changes location. When the interior is dark, it is forward, against the vertical chrome bar. As the interior gets brighter, the shot from the back seat looking forward shows the speaker is completely missing. When the interior gets really bright, inside shots show the speaker is a few inches rearward from the original location while exterior shots show its move even further forward. And when dark again, the speaker is where it was at the start. (00:47:40)
Deliberate mistake: The scene where Arnie takes Denis for a high-speed ride was obviously shot in a studio. Arnie throws an empty beer can out of a car doing 80+mph, so the window was rolled down - but his hair isn't ruffled at all. Alternatively, he used concrete as hairspray.
Factual error: When Arnie goes to visit Dennis in the hospital, on Thanksgiving, the date November 23 is shown just before the camera pans across the TV which is on and it shows the Oakland Raiders playing the Detroit Lions. That year the Lions played the Broncos on Thanksgiving. Three days later, on Sunday, the Raiders played the Seattle Seahawks. That Season though the Lions did play the Raiders on November 19, which would have been 4 days before.