Continuity mistake: Near the end of the episode, Joe and Quagmire are shown sitting at a booth inside the bar with Joe pulled up to the corner of the booth. As Peter apologizes to them, Joe is no longer seen next to him. As Peter takes Quagmire's check, a part of Joe is seen sitting in the next booth. In the shot after, he disappears again for the rest of the scene.
Three Kings - S7-E15
Factual error: Stewie shoots Joe with a double barrel gun. He shoots at him 3 times without reloading. (00:12:50)
Factual error: When Stewie writes in his notebook he actually never opens it.
I Am Peter, Hear Me Roar - S2-E8
Continuity mistake: Peter complains about having to spend a week at a women's retreat for sensitivity training, but when he returns, the caption reads "two weeks later."
Continuity mistake: When Stewie mentions to Brian about his "Life's a beach" mug, the squares on his calender keep changing size.
Mr. Griffin Goes to Washington - S3-E3
Factual error: Neither the Lincoln Memorial nor the Washington Monument are visible from the East Front of the Capitol. Furthermore, the Lincoln Memorial is shown as being northeast of the Capitol, when in fact it is due west.
Continuity mistake: When Brian is at the psychiatrist's for the first time, the psychiatrist's chair changes position between shots. (00:08:20)
Continuity mistake: When Connie and her friends walk up to Peter (as Lando) graffitying, the black guy changes position between shots. (00:09:55)
Continuity mistake: After Lois says that Stewie is the 'president of poopy' she and Tricia change position in relation to the couch. (00:09:30)
Factual error: Peter is posing as a blow up sex doll. The tester picks him up like he doesn't weigh anything. Not possible.
Continuity mistake: Peter falls from the roof of the Clam landing on Joan Cusack. He puts her body in a mailbox that appears just for this scene.
Road to the Multiverse - S8-E1
Other mistake: In every universe - except for the double-headed universe - Brian and Stewie travel to, they (seem to) replace the version of themselves that universe already has of them, but then in the Dog universe they have a separate version of themselves that they continuously interact with.
Ocean's Three and a Half - S7-E7
Factual error: Bonnie changes Susie and Joes diaper. There's no way Joe wears the same size diaper as Susie.
Boys Do Cry - S5-E15
Other mistake: Towards the very end, they automatically head to the car, planning to leave Texas, without any of their items from the house packed in the car after running away from the mob at the Miss Pageant Contest.
A Picture Is Worth 1,000 Bucks - S2-E11
Other mistake: Brian says he met Antonio Monatti when he was with Andy Warhol in the '70s. This is an impossibility. Only several episodes earlier (in episode Brian in Love), we find out that Brian is 7 years old.
Continuity mistake: When Peter winks at the camera wearing an afro, it is black, but when he sits back down, the afro is brown.
Something, Something, Something, Dark Side - S8-E20
Continuity mistake: When Han lands the Millennium Falcon in the "handicapped" crater on the asteroid, the handicapped parking logo disappears from the ground. (00:22:45)
Continuity mistake: All the army men including Brian and Stewie have USA symbols on their arms, but when Stewie and Brian talk to one of them, after they shoot each other in the foot, the USA symbol on the man's sleeve is orange lines and a arrow.
