Plot hole: When Stewie and Brian are at the diner Stewie says he negotiated a deal with the mob by telling them he convinced Mort to give him his flash drive with the info to put the mobsters in prison. When they actually meet, Stewie tells the mob guys the flash drive is "his" and that he bought the coverage. Then he says his address is on the drive so they can mail it back to him. The mob guys didn't realise Stewie lied about whose flash drive it really was. (00:15:40 - 00:19:00)
Stewie, Chris & Brian's Excellent Adventure - S13-E7
Factual error: In the episode, the Titanic is shown to have sunk the same day it left England. The actual Titanic left England on April 10th and didn't sink until the night of April 14th, almost four days later. (00:11:40 - 00:15:30)
And Then There Were Fewer - S9-E1
Other mistake: When everyone is leaving the mansion after Stephanie was killed, 3 mistakes happen at the same time: Dr. Hartman came alone, but there is a person sitting in the front seat next to him. Derek is in the car he and Jillian came in when they got here, but he is alone. And Carl was getting into Herbert's Ice Cream Truck, which was in front of his own truck.
Factual error: In the bit when Brian and Stewie are in Poland, the sign they are looking at should say Warszawa, not Warsaw.
Continuity mistake: The bullet holes in Lois keep changing place between shots. This also happens during the flashback in the courtroom.
Herpe, the Love Sore - S12-E16
Factual error: Stewie could not have gotten herpes by blood - it's only transmitted by infected saliva or skin.
Suggested correction: Please tell me that you are not a doctor! The two types of herpes viruses, HSV1 and HSV2 can be transmitted in blood as well as saliva. Such transmission is very rare as the virus deactivates rapidly in stored blood, but it is incorrect to say that it cannot happen.
The Cleveland-Loretta Quagmire - S4-E5
Plot hole: Brian and Peter see Loretta and Quagmire having sex yet, they aren't sure who she's having an affair with. There's no way they couldn't have noticed it was Quagmire - the couch was facing the front door! And obviously Quagmire was on top of Loretta considering the fact that he leans up, says something, then she tells him to get back down here and finish.
A Very Special Family Guy Freakin' Christmas - S3-E16
Continuity mistake: Prior to the family opening their presents at the end of the episode, there is a shot of the outside of the home. Notice the right window intact. Cut to a shot inside, the window is still damaged from earlier in the episode.
Brian's Got a Brand New Bag - S8-E4
Continuity mistake: Towards the end of the episode, we see Rita's bedroom door opens in. When Brian returns from the store, there's no door at all. When he leaves, the door opens out because he slams it shut.
And Then There Were Fewer - S9-E1
Other mistake: When they are chasing Tom around the dining table, they huddle up in a circle. Everyone is looking at Peter talk, and when Doctor Hartman says "Damn, that is awfully risky," if you look at Carl's eyes, they clip outside their eyes to look at Hartman.
Continuity mistake: At the end of the episode, Connie kisses Stewie. Her book and Stewie's clothes disappear from the floor when Connie is taken away.
Screams of Silence: The Story of Brenda Q - S10-E3
Continuity mistake: When Brenda arrives at her intervention, she sits down and puts her purse on the floor. It disappears for the rest of the scene.
Stew-Roids - S7-E13
Continuity mistake: When Lois is talking to Meg on her bed she gets up and throws a book and a bottle of pills on the bed that came out of nowhere. The nightstand is out of view but if you look at the earlier scene there's nothing on the stand except a clock and a lamp.
Brian Goes Back to College - S4-E15
Continuity mistake: When Brian arrives at Brown, his bag strap is across his body. When the shot changes, it's just on one shoulder. (00:08:00)
Brian Goes Back to College - S4-E15
Continuity mistake: Louis' hand changes places on the newspaper at the start when talking to Brian. Note its position in relation to the column. (00:02:10)
Continuity mistake: In the first shot of the pool party, Peter's "President" sash is draped from his left shoulder with the visible letters "n" and "t" in reversed positions. In the following shots the sash is draped correctly from Peter's right shoulder.
Continuity mistake: At the IRS, when Peter walks into Stratford's office there is no light switch beside the doorway, but a 3-gang rocker light switch appears in following shots.
Continuity mistake: While Peter is with Mayor West at Town Hall, when Peter winds up in the trap door, the doorknob on West's office door changes sides (so the door opens the opposite way) and the plant moves away from the corner.
Continuity mistake: When Peter's great-great uncle, Ulysses S. Griffin, is with Robert E. Lee, all the Confederate soldiers have their straps over their left shoulders, but in the closeup two soldiers have their straps over their right shoulders.
