Plot hole: Al comes home from work. He purposely doesn't look in the kitchen, so he can act like he's surprised it isn't Peg that brings him a beer. Steve talks and Al acts surprised that he's there. When you walk in the front door you automatically see the kitchen.
Suggested correction: It's quite possible to do this. My house has a similar layout: front door opens into the living room, and the kitchen is at the back of the living room. I can come inside and walk to the couch without paying attention to the kitchen. Plus, Al is cranky after work - he says "Ah, what a day" - and he is focused on getting to the couch and relaxing.
This is the only episode where Al does this... Just because he knows it's Steve and not Peg. Pretty obvious.
Just because something is only shown in one episode, that doesn't mean it has never happened before. And because he said "What a day", it seems that his work day was especially frustrating, busy, etc. It's reasonable that he could focus on getting to the couch, not bothering to look at the kitchen.
Continuity mistake: Marcy tells Peg that Steve has been gone for 5 days. Yet when he gets home, he has grown a full beard. It would take longer than 5 days to grow a full beard like that.
Revealing mistake: When the mall Santa lands in the Bundys' back yard, everybody looks toward the back, and when Al looks forward, he cracks a smile although he's upset about the matter. Ed O'Neil admitted he couldn't contain his laughter.
Build a Better Mousetrap - S2-E15
Continuity mistake: When Al hits his thumb with the hammer when trying to hit the mouse in the wall, he hits his left thumb. In the very next scene, Peggy is wrapping up his right thumb.
Build a Better Mousetrap - S2-E15
Revealing mistake: Al smashes his finger while holding a piece of cheese next to the hole in the wall. But you can see the hammer wasn't near his finger at all. It hits the wall.
Master the Possibilities - S2-E16
Factual error: Buck may have got a credit card in the mail but Al would've got jail time for credit card fraud considering he signed Buck Bundy on all the receipts.
Master the Possibilities - S2-E16
Factual error: A credit card company doesn't send random cards to just anyone. One comes for Buck. First of all you need a social security number, proof of income etc. And looking at what Al and Peg bought, it's an unlimited card.
Suggested correction: Decades ago (including the 1980s when this show aired), credit cards were sometimes sent to almost anyone - or "anything", such as a family's dog. People used to joke about actually getting a credit card for their cats, dogs, infant children, etc. Credit card representatives also went on campuses to lure "unemployed" students into getting credit cards by offering a free gift. They hoped college students would buy what they wanted or needed and parents would bail them out (pay the bills).
Suggested correction: It should be pointed out that credit card companies, especially in the past, do send out random cards (and offers). They buy customer information from stores from various sources, like warranty cards. People who have received credit cards for their pets (which has happened) have often filled out warranty cards with their pets' name but the rest of the information is the person's.
And some of the "less than honest" recipients of unsolicited credit cards were able to use the cards practically immediately, so went on shopping sprees and charged thousands of dollars for whatever they wanted with no intention of paying or being identified. And not all college students had parents that would bail them out, resulting in huge losses. It took a while, but the credit card companies learned from their mistakes and made drastic changes to avoid getting ripped-off in the future.
Peggy Loves Al, Yeah Yeah, Yeah - S2-E17
Other mistake: When Bud goes upstairs with his fake bag of "Valentines" (actually a bag filled with bottles), Kelly begins to look through some from her bag. Behind her, you can see David Faustino (Bud) purposely moving slowly up the stairs because Christina Applegate (Kelly) is about to find the envelope that is addressed to Bud.
Im-Po-Dent - S2-E19
Revealing mistake: Bud and Kelly put Tang in glasses. Al says "what are you hiding?" They quickly "drink" it but the glasses are empty.
Just Married ... With Children - S2-E20
Other mistake: Al gets sat on by 3 heavy women. The scale says 927 pounds. 4 more women sit down and the scale says 1071. So 4 more heavy women only added 144 pounds? Impossible.
Just Married ... With Children - S2-E20
Other mistake: Al and Peg win a new Mustang in this episode. It's never seen again.
Just Married ... With Children - S2-E20
Factual error: In the game show near the end, when Marcy and Steve come out as Al and Peggy. When the real Al and Peggy win the car, because they used Marcy and Steve's names, the car would have never gone to the real Al and Peggy. In reality, it would have gone to Steve and Marcy because it was won under their names. Al and Peggy would not have been able to keep the car. In fact Al and Peggy would not have been allowed to be on the show at all using someone else's name.
Just Married ... With Children - S2-E20
Revealing mistake: When Al spins Peg on the wheel to win the bowling ball, in the long shots, you can plainly see its not really Peg on the wheel. It's a dummy.
Continuity mistake: When young Al reaches forward with his left arm to take the book that Miss Degroot wants to give to him, she quickly pulls back but young AL still has his arm raised. In the next shot, his hand his down by his side.
Revealing mistake: At the start of the episode, Peg is making popcorn on the stove. It's making a sizzling sound like she's really popping it but the burner isn't even on.
Revealing mistake: Peg is making popcorn on the stove. It pops even though the burner isn't even on.
The Bald and the Beautiful - S3-E7
Other mistake: At the end of this episode, there is a typo in the credits: "Directed by" is written twice. (00:22:30)
The Bald and the Beautiful - S3-E7
Other mistake: Al and Steve are using Dr fur for growing hair. After using it, Steve says it was recalled. Later in the show, Peg says she is going to the store to buy Dr Fur because it was the only thing that Buck would eat. If it was recalled it wouldn't be available to buy anymore in the store.
I'll See You in Court - S3-E10
Continuity mistake: While they are in court, Steve is talking about the case and the clock says 12:30. Next time he's seen and talking about privacy to the jury, the clock says 11:30. Then when done talking, the clock says 3:00. The very next scene as the court proceedings are going forward, now the clock says 12:29. Next scene says 4:32. Than backwards again. The clock is moving forward and backwards throughout the entire scene.
Eatin' Out - S3-E11
Revealing mistake: At the end of this episode, Bud supposedly has a lemon frozen to his mouth but he plainly is just biting down on it. Then Al uses his lighter to "unstick" it, but Bud just spits it out.
