The screenshot showing Homer's pumping gas directly into his car trunk was authentic, and came from a 2010 episode.
Homer's pumping gas into his car trunk had nothing to do with any gas shortage in the episode in question; and in any event, several gas shortages had taken place before 2010, meaning there was no question of a "prediction" occurring.
In May 2021, as parts of the United States experienced a gas shortage caused by a cyberattack on the Colonial Pipeline, internet users shared what appeared to be a moment from an old episode of "The Simpsons," as yet another example of the show's writers' "predicting" future events.
The screenshot showed Homer frowning as he filled the trunk of the family's car with gasoline, straight from the pump, and one user of the image-sharing website Imgur added: "The Simpsons predicted it again..."
The Colonial Pipeline cyberattack triggered panic buying of gasoline in several states in 2021, prompting the U.S. Consumer Safety Commission to warn the public not to fill plastic bags with gasoline, or otherwise use inappropriate containers (such as the car trunk shown in the "Simpsons" screenshot) to store gasoline.
The screenshot of Homer pumping gas directly into his car trunk was authentic, but in proper context it had nothing to do with panic buying or a gas shortage. Furthermore, several gas shortages had already taken place in the United States before 2010 — most notably during the 1970s — so the notion that an episode of "The Simpsons" from that era had "predicted" that a similar event would occur in 2021 did not make sense. We're issuing a rating of "Mostly False."
The episode in question was "Lisa Simpson, This Isn't Your Life" — the fifth episode of Season 22, which aired in November 2010. Towards the beginning of the episode, Maggie, the baby of the family, is desperate to collect the rare "Baby Must-Have" toy, hidden among thousands of boxes of "Happy Little Elves" figures sold at "Texxon" gas stations, a sponsor of "The Krusty the Klown Show."
Homer, determined to make his daughter's dream come true, visits numerous Texxon gas stations in and around Springfield. When he is told he must buy 10 gallons of gasoline for every "Happy Little Elves" box he purchases, he sets about using up gas as quickly as possible: doing donuts in the gas station forecourt; hitting the accelerator while the car sits on breeze blocks; and, eventually, filling the trunk with gas, as shown in the screenshot below: