Pump prices plunged $1.40 a gallon at a notoriously expensive north Torrance Arco in the wake of a Daily Breeze article earlier this week that went viral on social media.

The price for a gallon of regular gas was $3.49 Wednesday, two days after the article reported that unsuspecting motorists were paying $4.89 a gallon at the 182nd Street and Crenshaw Boulevard gas station that sits opposite a freeway exit and entrance.

The reduced price, which readers said was first posted Tuesday, was still among the highest in the city, but at least it wasn’t as much as $2 higher than most other area gas stations.

“It’s amazing,” said a chuckling Geoff Nielsen, a Redondo Beach resident whose daily commute takes him past the gas station.

“That gas station hasn’t changed prices in a year,” he added. “Sure enough, the day after your story, the price goes down $1.50.”

Still, why the gas prices dropped — or, more to the point, why they were so high in the first place — remains unclear.

A man who answered the telephone at the gas station when a reporter called and asked for the owner declined to provide an explanation.

“I don’t know the story, but that thing is over,” he said vaguely. “We told you we were going to put the prices down.’

A call placed Wednesday to San Antonio-based Treasure Franchise Co., a subsidiary of Tesoro Corp., which owns the property, was not returned.

Still, grateful motorists who contacted the Daily Breeze via email weren’t complaining.

“I have wanted to know what their story is, but didn’t know who to contact about it,” wrote reader Marie Royal. “Even if they eventually get in step with the other stations, I won’t ever buy gas there again. Thanks for looking into this mystery — which is now an even bigger mystery!”

Indeed, the infamous gas station, known for being deserted even during rush hours, wasn’t particularly busy Wednesday. Over the years, motorists were left especially perplexed by the previously sky-high prices because Arco generally has a reputation for inexpensive gas.

“I drove by it today and thought it was funny,” reader John Ross Gatlin emailed of the suddenly cheaper gas. “Thanks for the entertaining article, by the way!”

Nielsen said he had called both Arco and Tesoro in the past about the exorbitant prices and received the same brush-off as the Daily Breeze. But, like Royal, he added that it’s unclear whether the gas station will ever reclaim his business.

“To me it was a personal slap in the face because I’m a consumer,” he said. “If I ever got off that freeway and needed gas I’d rather get my car towed.”