Revealing mistake: When Aaron is pinned down by the sewer zombie, the zombie actor's neck can be seen below his head mask.
Suggested correction: I went back and watched this scene several times, and I think the OP is mistaking Aaron's hand on the Walker's neck as the gap in the mask.
Pretty Much Dead Already - S2-E7
Continuity mistake: As the group kills the walkers that come out of the barn, the camera shows several different vantage points from in front of the barn, inside of the barn etc., it shows the walkers lying with a clear path between them, and in another it shows the walkers lying in a jumbled pile with no path between them. This goes back and forth a few times until Sophia comes out of the barn, and there is no clear path again.
Continuity mistake: When the Winnebago breaks down. Shane and T-Dog offer to drive ahead to check out what could possibly be a gas station. Shane tells Rick to hold the fort while they're gone. Meanwhile Rick is dealing with dying Jim. When discussing Jim's predicament, Shane is there, he hasn't gone anywhere. Then when they put Jim under the tree T-Dog is there too. Then they all drive off like the breakdown never happened. Nothing is mentioned about whether Shane and T-Dog found a gas station and if they did, it was very quickly sorted out - two minutes tops. (00:31:00)
Continuity mistake: When Rick, Carl, and Michonne are leaving King County (Rick's home), they must travel around a wreck involving two cars and an overturned RV. They drive along one side of the road. When the camera angle changes, they are on the opposite side of the road going the other way. (00:41:30)
Visible crew/equipment: Andrea and the crowd are at Woodbury main gate arguing, when they hear a woman, closely followed by a man screaming up the street. Andrea and a lookout start to run up the road, where there is a woman running down the road. A sound-man in white shorts and red shirt, holding an overhead boom mic, is visible as he starts to jog down the street, tracking the woman as she moves towards them. (00:20:55)
Visible crew/equipment: Negan and Carl go for a ride in the big truck. Daryl tells Negan not to harm Carl and he flips him off. In this scene, the camera tracks upward and its shadow casts on the truck. Also a film light can be seen reflected in the door jam.
Continuity mistake: When Mica and Lizzie are running from the walkers on the railroad tracks, they easily outrun them and gain several meters' distance in a few seconds. When they are running to the house, the walkers have suddenly caught up and are directly behind them.
Revealing mistake: When Carl rolls out the knife pack he found, the scene cuts to Shane working on the engine, and you can see traffic on a highway through the bottom of the windshield. (00:33:00 - 00:34:00)
When the Dead Come Knocking - S3-E7
Continuity mistake: The first shot of Maggie waiting for the Governor to enter shows her wearing a black tank top with her shoulders bare. After he cuts the duct tape around her wrists, the camera pans up and she now has black bra straps showing on her shoulders. (00:26:10)
Other mistake: When Daryl is cutting open a walker in the woods to see what meat it ate while searching for Sophia he stabs the walker several times, but the knife is not bloody and it stays clean. (00:33:30)
Continuity mistake: When Glenn is with Tara and getting ready to move out, he puts on his helmet and you can see it is strapped on. When the shot changes, he swings the fence open and you can see his strap is lose. The camera angle changes again and the strap is back on again. (00:38:15)
Visible crew/equipment: When the car flips in the chase scene, you can see the round canister used to flip it. (00:10:25)
Internment - S4-E5
Continuity mistake: When Rick gets out of his car and talks to Maggie inside the prison gates. The car door opens and shuts throughout the conversation.
Continuity mistake: In the flashback to the prison, Hershel says "we've been here two months." However, when they show Judith she is shown to be the same age she was when the prison fell (around 9-10 months) If they had only been there two months, and Lori delivered within the first week of being there, the baby should not be very old.
Chupacabra - S2-E5
Continuity mistake: During the scene where Norman Reedus is talking to Michael Rooker, watch the dirt and sand around Reedus' mouth appear and disappear during the talk while he is on his back.
When the Dead Come Knocking - S3-E7
Audio problem: When Rick and his 'strike force' hole up in the cabin surrounded by walkers. They arouse the cabin's owner who brandishes a double-barrel, breech breaking shotgun. When characters brandish pump action shotguns, often they pump a round for effect and the sound effect is characteristic. The pump action sound effect is erroneously applied to the breech breaking double barrel shotgun.
Continuity mistake: In Season 2 episode 7, "Pretty Much Dead Already," at the end where Rick shoots the walker Sophia, she falls to her right. In the next episode, "Nebraska," picking up immediately after the last, she is in an entirely different position, as if she fell forward.
Factual error: Ten minutes into the episode, where they're setting up their police-blockade, a cop makes a remark about being in some TV-show when Rick Grimes replies with: "Make sure you've got a round in the chamber and your safety off". Next we see the first cop checking his gun (a Glock) for a round in the chamber and we see him flicking his thumb across the gun's slide catch: not a safety-lever. Glocks don't have an external safety, so the cop cannot flick a safety-lever like in the episode. (00:10:10)
Factual error: The supposedly American tank Rick crawls into in Atlanta has US markings but is a British Chieftain.
