Continuity mistake: When Kelly is at the grill, right after being called a "dullard" by Bud, Kelly grabs Bud's wrist with her left hand. As we pan out on the exact same scene, her hand is nowhere near his wrist.
Factual error: Al uses ashes to cook food on the grill. You can't just throw ashes in a grill and light them! They wouldn't light at all. That's like trying to light cigarette ashes and expecting them to burn hot enough to cook food.
Dead Men Don't Do Aerobics - S4-E2
Other mistake: Jim Jupiter stays with Peg for a week. 6 days later he's shown heavier than he was before. You don't gain that much weight in 6 days.
Dead Men Don't Do Aerobics - S4-E2
Revealing mistake: When we see Jim Jupiter on his show after gaining weight, you can plainly tell he's wearing padding under his clothes to make him look fat.
Continuity mistake: Al takes the kids camping. When he leaves the house, his shirt is light blue. When he comes out from the bushes in the woods, it's dark blue with red stripes.
Plot hole: Al can't eat because his mouth is numb. So they go ahead and eat. Al can eat after the novocaine wears off and Peg can put leftovers in the fridge. They all act like Al can't eat for days and there won't be any food left.
He Ain't Much, But He's Mine - S4-E5
Plot hole: Marcy gets her hair done like Pegs. Everyone makes fun of her saying she looks ridiculous. All she has to do is wash it! Its obviously held up with hairspray but Marcy acts like there's nothing she can do about it.
Desperately Seeking Miss October - S4-E7
Revealing mistake: In the scene where Al and his Dad (both played by Ed O'Neill) are sitting on the couch side by side watch the lines of the cushion in the middle. Every time one of them moves you can see where the two separate shots are overlaid. (00:14:15)
Factual error: The sheriff does not come to your house and take your credit cards just because they are maxed out. The only time they would do that is if you stole someone else's card and were using it.
At the Zoo - S4-E10
Other mistake: Marcy knocks at the door, and Steve is inside. He tells Peg to stall her so he can go out the back door. She can obviously hear everything he's saying.
Visible crew/equipment: After Al fixes the roof and Peg reminds him to fix the TV antenna, when Al says he can do it, a shadow can be seen moving across the blue bucket on the table. (Probably a crew member or equipment.)
Factual error: Peg says she did the taxes and claimed 23 children. First of all, you can't. Max number of dependents is 2-3, and second you have to have birthdates and social security numbers for everyone. You can't just write whatever you want and send it to the IRS. And it's a joint return yet Peg says she didn't sign her name. You have to. So in reality, she would get in trouble too since she actually lied on the tax return.
Continuity mistake: A lady agrees to buy some of Peg's red hair. It shows the lady with two baggies with red hair in them, but at the end of the episode we see that they used Buck's hair, which is far from being red in color, or anything like human hair.
Deliberate mistake: When the family is trying to get money from Al at the start of the episode, he throws it on the ground making the rest of the family to dive on it and you can see Bud get it, then throw the bunch of money in the middle of Kelly, Peg and Bud so they can all get to it instead of taking it all. (00:02:10)
Continuity mistake: When Kelly blows up the car near the end, when they show the car before it explodes, you see someone walking on the right side behind the car. Half a second later the car explodes and now someone is walking by the building on the left side of the screen. There wasn't anyone there before.
You Gotta Know When to Fold 'Em (2) - S4-E17
Plot hole: Al hasn't got enough cash to pay for a pizza and Peggy overmaxes his credit cards. But somehow he manages to buy three flight tickets for Chicago-Las Vegas. Where'd the money come from? Also, when his card is declined, he calls the pizza shop back (they call him "no tip" Bundy), and somehow they know where Peggy maxed out the credit card. (00:05:15)
You Gotta Know When to Fold 'Em (2) - S4-E17
Factual error: Bud and Kelly wouldn't be allowed to go in a casino in Vegas because they are both under 21.
Other mistake: When Peggy throws the final ball, all the pins fall except for one and the sweep bar comes down. It is then shown wobbling down without the sweep bar in play. This is an illegal drop and would not count under any PBA sanctioned tournament or in any bowling alley in the United States. The bowling alley would credit her with a 299, and Al would have a chance to get a 300.
Plot hole: In this episode Al is about to break Puggy Weaver's record. Peg decides to bowl and scores a perfect score of 300. Problem is Peg is a horrible bowler, as seen in season 2 episode 9. She never bowls with Al or even enjoys bowling, so this episode really makes no sense.
Suggested correction: This is not a plot hole, but a plot point. Yes, Peg is a horrible bowler, but it's typical Al Bundy luck that his wife would be able to put together a perfect game no matter how unlikely.
So this one and only episode she scores a perfect game? Highly unlikely. Oh and she's wearing a long evening dress too which would make it difficult to bowl. So this episode makes no sense.
It makes perfect sense. In the world of the show, the universe is out to screw Al over. The worst that can possibly happen to him will happen no matter how unlikely.
It is a comedy, so having all those "strikes" against her, she still managed to bowl a perfect game - leaving Al hopeless and hapless.
Revealing mistake: Kelly is standing by the clock on the stairs. You can see Al and Peg's shadow on the wall waiting for Kelly to come up the steps, so they can come down. (00:02:59)
