Other mistake: Al's and Peggy's birthdates are around 1948/1950, respectively. Supposedly, Al married Peggy after she got pregnant the day of his 4 touchdowns in high school in 1966. How could Kelly have been born in 1971?
Other mistake: When Steve wants his money back, Al asks how much was Steve bragging about earlier ($5) he could take and make a fortune, instead of giving Steve $5 it's a $20 bill.
Revealing mistake: Marcy dries her dress in Peg's dryer. She comes downstairs with it on looking like it shrank. You can plainly see Marcy put on her belt and pulled up her dress to make it look shorter.
Continuity mistake: Marcy says her parents never let her have a Barbie as a child. In Season 2 episode 14, Guys and Dolls, Al and Steve steal Marcy's Barbie from the basement to sell to buy a new baseball card.
Other mistake: Al, Peg, and the kids go to the beach. Steve and Marcy are sitting not too far away from them, yet they never interact with each other. They had to see each other they just act like they don't notice each other.
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.
Continuity mistake: The out of order sign on the toilet changes position between shots. It's level at first. Camera cuts to other men. When it cuts back to Al it is tilted. (00:18:18)
Movie Show - S7-E21
Revealing mistake: When Kelly is eating the boxes of candy you can plainly see they are empty, but she's chewing anyway.
Revealing mistake: Kelly lost all her hair as a side effect from pimple potion. You can see the lines on her forehead that show she's wearing a flesh piece covering her hair to make her look bald. The color is lighter than her face. (00:18:42)
The Chicago Wine Party - S7-E7
Character mistake: Throughout the entire episode, they talk about the beer tax being 2 cents. At the very end when Terry is doing her on air broadcast, she calls the tax a "2%" tax. There is a big difference.
Tis Time to Smell the Roses - S7-E23
Other mistake: When Al talks about the man who bought the shoe store he wanted to buy, he says the same guy bought the store he used to work at and got his old job back. However, Gary is a woman who owned the store before this episode and again afterwards for the remaining episodes. So it couldn't have been bought by a man because Gary the woman still owns it.
Character mistake: When Bud is showing Al his school project of a fan page turner, he has it on the left side and blowing the pages left to right. That would be blowing the pages the wrong direction to flip pages. It should be on the right side changing pages right to left.
Girls Just Want to Have Fun (1) - S2-E5
Continuity mistake: Al is having his fridge repaired. He goes and gets a beer and closes the door. A few shots later the door is wide open without anyone going near it.
Continuity mistake: Marcy's niece asks Bud to take a shower so she can get out of her sticky clothes. Next scene, she's sitting on the couch with a towel on her head. She talks to Bud awhile then gets up and leaves. Shes wearing the same "sticky" clothes and she takes the towel off her head, and her hair is completely dry.
You Better Shop Around (1) - S5-E21
Continuity mistake: When the store employee comes over to ask Al and Peg what they were doing, Peg throws a bag of chips in the shopping cart and says shopping. When Al asks Peg what the ingredients are, next shot the bag of chips are on Peg's lap.
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.
Plot hole: Outside the Savoy, Marcy tells Jefferson that at last, they found the Bundys. How did they know that the Bundys were there? The Darcys had not been in touch with them since they were left behind at the airport, and the Bundys only decided much later that they were going to the Savoy.
Revealing mistake: When Al slams Kelly's date's head on the banister it moves back and forth indicating it's made of rubber.
Poppy's By the Tree (2) - S2-E2
Plot hole: Al and Peg are upstairs with the killer. Both of them are screaming, but downstairs, you can't hear anything. Everyone is sitting around talking. It's not until Al and Peg scream again that everyone runs upstairs. And you can tell the screams were "on cue" also.
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.
Answer: It was one of the hoses connected to the engine, nothing specific, but to indicate that Al tampered with the vehicle.