Continuity mistake: When the T-800 arrives between the tractor-trailers, you can see a bumper sticker (i.e. "Vehicle makes wide turns") on the back of the trailer when the sparking begins. When Arnie arrives in the bubble it "melts" out the back corner of the trailer, and the sticker is no longer there. (00:05:50)
Continuity mistake: In the shot where T-800 arrives in the time bubble, the bubble removes a clean cut chunk of the rear end of the truck. If you look at the very center of the wheel that is cut in half, there is part of the axle right at the tip of that wheel which is not cut. (00:06:25)
Revealing mistake: In the scene when the T-800 first comes through the time machine, in the shot where he stands up. If you look towards the right side of the bowl shape that's melted into the ground, you can see that the bowl shape is actually above ground. There's a shadow being cast by it on the right side. (00:06:30)
Factual error: When the T-800 is scanning the parking lot in the bar near the beginning of the movie, he scans the lone car parked outside and his display reads "Plymouth sedan." The vehicle he scanned was a Ford LTD Crown Victoria. (00:06:50)
Revealing mistake: In the beginning of the film, when the biker is thrown onto the stove you can clearly see the valves where the steam is coming from - it's NOT from his hands. (00:08:00)
Continuity mistake: In the scene where the Terminator is nude in the biker bar, one biker stabs him. The Terminator then grabs the knife with his left hand and twists the biker's arm. Then the Terminator uses his right hand to hold the biker's arm down on the pool table while still holding on to the knife with his left. Immediately in the next shot, the Terminator right arm is in the air with the knife in his right hand and stabs the biker. (00:08:05)
Revealing mistake: In the bar fight scene the Terminator gets stabbed by one of the bikers - if you watch carefully you see the rubber knife bend in one shot. This has been digitally fixed in the 2017 Blu-ray/4K release. (00:08:10)
Continuity mistake: During the bar scene, the Terminator is stabbed in the chest. You can see that he gets stabbed exactly above his right nipple. A few shots later, when he goes in the kitchen to get the biker's keys, the cut with blood dripping appears on his ribcage far below the nipple. (00:08:20)
Continuity mistake: In the bar scene after the biker burns the Terminator's chest with the cigar, it leaves a burn mark. Another biker comes behind him and hits him with a pool cue-the burn mark has disappeared, and then re-appeared in the next frame when he grabs that biker. (00:08:20)
Continuity mistake: After The Terminator exits the bar in the beginning and takes the gun from the bar owner while advancing towards the owner he takes his left hand off the barrel. From behind though, he's still gripping it. (00:09:20)
Continuity mistake: When the T-800 grabs the shotgun off the bar keeper,he cocks it (fully), then in the next shot, you see him half-way through cocking it. (00:09:30)
Visible crew/equipment: As the Terminator gets on the bike at the start, the barman comes out and fires a shotgun. Look in the bike's mirrors to see some film crew moving around. (00:09:30)
Other mistake: During the bar scene when the T-800 is on the motorcycle and the bar owner comes out and fires the gun, Arnold Schwarzenegger flinches, specifically his eyes close. (00:09:30)
Visible crew/equipment: When The Terminator exits the bar, a bartender then points a 30-30 at him. The Terminator then takes the 30-30 off him and takes a pair of sunglasses out of his shirt pocket. A reflector screen is visible in the reflection of the glasses when he puts them on. (00:10:10)
Audio problem: In the scene with John and his friend in the garage when his adopted mom is telling him to clean his room and he is revving his dirtbike, if you look closely, he has the throttle wide open, but the motor winds down. (00:12:15)
Continuity mistake: The scene where John and his buddy hack into the ATM and get cash, John is telling his friend his mother is a psycho. Watch closely as John puts on his backpack twice. (00:17:50)
Visible crew/equipment: Juat after Sarah gets a visit from Reese, she runs down a corridor and ends up outside. If you look carefully at the bottom left as the door opens, there's a guy's arms visible, making sure the door doesn't open too far. (00:21:30)
Continuity mistake: The amount of ash on Sarah's cigarette during her review changes instantly. (00:23:20)
Revealing mistake: Early on in the film, the T-800 sees John riding down the aqueduct. He stops, and a blue car skids and is hit by another on its right side near the rear wheel. As the T-800 sets off in pursuit of the T-1000 and John, a blue car skids and is hit on its left side. Guess what? Its the same car as earlier. You can tell by the massive dent above the rear wheel. (00:29:20 - 00:34:40)
Audio problem: In the scene where John is running away from the T-1000 in the corridor of the mall, one of the curators shouts out "Hey!" The Terminator appears in scene so John runs back the other way passing the same curator he ran past before who then shouts out "Hey!" at him again. The curator's mouth never moves during both of his lines. (00:31:30 - 00:31:53)