If you are looking for gas deals in the Puget Sound area, your first stop might not be General Brushless Car Wash, the family-owned Everett establishment with a bucket-headed mascot.

But that is where, on Thursday, a lucky driver could find a gallon of gas going for just $3.76 — well below the state average of $4.08 and 38 cents cheaper than the average price of gas in the Seattle metro area, according to AAA data.

So how does owner Mark Hoidal keep prices so low, while Washington still carries the dubious distinction of having the most expensive gas in the contiguous 48 states?

Since the carwash is not tied to a particular brand of gasoline, Hoidal said he isn't wed to a particular brand-owned refinery. Instead, he relies on his gas supplier, PetroCard, to buy gas on the more volatile, but currently cheaper unbranded market.

"All that the public cares about is the price on the street," he said, explaining the decision to sell unbranded gas.

All gas sold in the country has to meet national quality standards, but branded gasoline can contain brand-name additives like Techron for Chevron stations.

The supply of gas on the West Coast is rising now that several previously closed refineries are back online, said Tim Hamilton, executive director of the Automotive United Trades Organization, a nonprofit group representing gas stations and suppliers in Washington. He said the unbranded-gas market usually experiences the price drop first, which is why Costco, Safeway and other unbranded stations often have the lowest prices in the state.

The benefit of being unbranded can be great when wholesale prices drop, but when they rise, they can send the price at the pump soaring.

"As an independent, you live and die with market volatility," said Tom Kloza, chief oil analyst at the Oil Price Information Service. "As spot prices and wholesale prices for gasoline go up or down, your cost moves very quickly."

For Hoidal, when prices are rising dramatically, he buys only half a truckload and waits for the price to drop, often letting his tanks run dry in the process. Once the price declines, he stocks up on a full load, while his competition may be stuck with the higher prices from a few days or weeks before.

"It is a guessing game," Hoidal said about the market for unbranded gas. "Sometimes it is just a flip of a coin."

Hoidal decided to take advantage of falling prices Wednesday and bought a full load, so he could continue to offer a low price. . Hoidal, who has owned and operated his business for 37 years, used to be affiliated with Texaco, but decided to go unbranded. Selling gas isn't his primary business — washing cars is, he told My Everett News, one of The Seattle Times' news partners, which reported on Hoidal earlier this week.

Hamilton, who runs the nonprofit trade association, said Hoidal's and other unbranded stations should enjoy the edge they have on the competition while it lasts.

"Sooner or later, the branded price will come down," he said. "But, right now, he is having his moment in the sun."

Javier Panzar: 206-464-2253 or jpanzar@seattletimes.com On Twitter @jpanzar