When Mel tries to stop Hanson from killing Michael, she drops her purse on the ground. Seconds later, as Hanson wrestles with Mel and flings her into the wall, her purse is no longer on the ground.
In some shots of the armored truck's machine guns, it's clear the ammo belts aren't actually being drawn into the guns.
When Michael is test driving the limousine, the majority of the footage is just recycled from the opening scene.
When the missile is shot at the limousine in the opening scene, the explosion is clearly adjacent to the car, not through the driver's door as shown later.
When Bonnie is supposedly showing Michael a list of past ArmorBuilt clients on the computer monitor, the text shown is just a random sequence of PRINT statements with no customer names whatsoever.
When KITT is on the test track, after the third round of machine gun fire from Hanson, the ricochet spark effects are still being generated off KITT's body for a few moments after Hanson has ceased firing.
The grenade launcher on the armored car is too small to have a magazine and fire as many grenades as it does. Even if the grenades were in a superimposed load, they would not be able to fit within the grenade launcher.
When Mr. Knight was testing the prototype car, a missile is fired at it, and K.I.T.T. says that the ETA is 2.3 seconds. It takes far longer than that for the missile to come close to the car.
When KITT was coming to rescue Michael from the paint drying booth a driver can be seen on the right front seat hidden under a cloth the color of KITT's interior during the overhead shot.
When Hanson is wheeling the hydraulic lift to KITT's back wheels, a crew member in a red shirt is reflected in KITT's rear fender.
When Michael parks at the test track, just as Eddie says "Got a minute to do some negotiating?", the entire camera crew is clearly reflected on the side of the car.