Revealing: When Old Biff hands Young Biff the Almanac, the book passes through the film split (the vertical bar that divides the windshield) perfectly because it was on a motorized rig. But the stand-in for Old Biff didn't hold his arm at the right height, so Old Biff's arm disappears into the bar that runs down the middle of the window while the book floats across to Young Biff.

Other: In the scene where Biff confronts Marty outside the swinging doors while Marty is watching himself talk to his 1955 Mom and Dad, you can see that Crispin Glover (George McFly) has been replaced with a look-a-like. There are other scenes where you can tell it isn't him, but this is the most prominent one. Glover wasn't in the 2nd movie due to him and the producers not agreeing to a movie contract. All the scenes you see him clearly were taken from the first film. (i.e. where Marty is looking at him through the binoculars at the dance).

Visible crew/equipment: If you look at the money case that Doc brings with him that has all the different types of money for each year, you will see where it says 1864 the reflection on the glass or plastic of what appears to be a tripod most likely for lighting.

Visible crew/equipment: When the DeLorean is flying behind Biff's car, you can see the wheels of the DeLorean rolling along the ground. This is evident when the car turns to fly away after Marty is deposited on the back of Biff's car.

Visible crew/equipment: During the hoverboard chase in 2015 between Griff and his gang and Marty, you can plainly see the wires holding the gang up on their hoverboards in the wide shots as well as on the Jeep Wrangler before it lands in front of Marty.

Visible crew/equipment: When Old Biff says, "Something very familiar about all this," a crew member is reflected in the restaurant window behind him.

Revealing: After Old Biff steals the DeLorean, he backs it up into a dumpster and several trash bags. The dumpster and the bags move before the DeLorean touches them.

Revealing: When Biff cocks his revolver in the alternate 1985, you notice that the chambers rotate in the wrong direction. This is either a flipped shot or a mistake caused by the prop gun.

Continuity: At the beginning of the second movie when Marty is checking out the new car, he audibly bangs the car with his fist right below the window frame. In the version of the same scene at the end of the first movie, Marty makes a similar hand motion but does not bang the car, and there is no noise.

Continuity: In 'Part 1,' after Doc crashes into the trash can, Marty waves his hand in front of Doc's torso. In 'Part 2,' he waves his hand in front of Doc's glasses.

Continuity: In the first BTTF at the scene were George Mcfly knocks out Biff and takes Lorraine, Marty sees them while he is standing in front of a couple. When he goes through the couple to get to the band performing at the dance, the woman in the couple makes a noise and gets pushed aside as he tries to get through them. In BTTF 2 when the Marty back from 1985 is watching George Mcfly knock Biff out before he steals the Almanac, the Marty from 1955 stands in front of the couple again, but this time the couple leaves a gap for him to go through, and when he goes through the woman in the couple, she makes no noise and doesn't get pushed. It was as if she was expecting it that time. As well, the couple isn't the same.

Continuity: Biff has exactly the same view towards the street as Marty and Jennifer, but the houses and cars on the other side of the street are totally different.

Continuity: During the dance hall scene, the first half of the guitar solo Marty plays (before the Eddie Van Halen section) is completely different to the one he plays in the original film. Whether this is just to give time for the jump sequence to take place or not is open to question, but all the same, although not many people would notice, it is a pretty obvious mistake.

Continuity: When the Delorean first lands in the alley in 2015, there is a shot of the back of the car as it lands. The large vents that extend out of Doc's modifications to the car are the wrong size. In most shots, they extend over the car's tail lights, however in this shot they stop above the lights. According to commentary this is a fiberglass scale model of the Delorean used to film flying scenes, since it is lighter than the actual vehicle, so apparently the model was not quite identical to the real Delorean.

Continuity: When Marty dries his jacket, the clock tower pillars are in the shade. But when he hands the hover board back to the girl, they are in the sun.

Continuity: The garage where Marty's truck is parked is very different in the opening scene of BTTF II than in BTTF I. The gardening tools on the wall to the left were different, and the brown wall siding in the back of the garage was not there in Part I.

Visible crew/equipment: When Biff and his gang are chasing Marty on the hoverboards in a few shots after Marty is hanging off the back of the Jeep, when the shot shows the gang catching up, the Jeep goes through some wet places in the street, showing the camera car's tire tracks. They're not the Jeep's because the tire tracks are double-wheeled and the Jeep was not turning in that shot.

Continuity: In Biff's apartment in alternate 1985 while Biff and Lorraine are arguing he knocks her to the ground and both her shoes come off. After Biff punches Marty in the stomach it then switches again to show Lorraine's reaction. As it does this we see her on the floor but her shoes are back on her feet. She could have had enough time to put them back on possibly but it seems unlikely that she would have done so as she is laying in the same position as when she was knocked down.

Continuity: At the end of the first film when Marty leaves the garage to greet Jennifer, he does not have a watch on throughout the whole scene. In the identical scene at the beginning of this film, Marty is wearing a black watch.

Continuity: Biff's 46 Ford changes from a convertible to a hardtop with the roof cut off during some scenes (notice the shape of the windshield frame and vent windows).