The Virginia attorney general's office charged yesterday that an Arlington service station is taking illegal advantage of customers during the gasoline crisis by forcing them to buy a car wash in order to purchase more than $5 worth of gas.

The office filed suit asking Arlington Circuit Court to order George Ryffel, an owner of Clarendon Amoco Car Wash at 3000 Washington Blvd., to stop requiring drivers to buy the $1.95 car wash.

The attorney general said the requirement violates the state's 1974 Antitrust Act because it takes unfair advantage of drivers who may feel coerced by the gas crunch into paying for a car wash they don't want or need. The act outlaws business practices that unfairly affect competition and penalize consumers.

Ryffel was out of town for the holiday weekend. His son, George Ryffel II, said the station is owned by a family company, Northern Virginia Associates Inc., and that the company added the car wash requirement a few weeks ago in order to accommodate regular customers at a time when the station's gasoline allocation has been cut 20 percent.

"It's a car wash and the gasoline sales are just a sideline," said Ryffel. "Our regular customers expect to able to fill up when they come to get their cars washed.But a lot of new people are coming in just for gas, and with our overhead, we can't survive unless they get their cars washed also."

Assistant attorney General John Russell Jr. said he sympathized with Ryffel's plight, but said his office feared the car-wash requirement could inspire other gas station owners to require oil changes or car repairs with fill-ups.

"It's been happening in California," said Russell. "The gas situation is getting to the point where this kind of thing can go on. We're just trying to nip it in the bud."

Russell said his office filed suit after the weights and measures section of the state Department of Agriculture and Commerce received several complaints from motorists. An official in the section called the car-wash manager earlier this week, but was told the requirement would continue until he was given "official word," according to Russell, who said, "we're here today to give him official word."

Russell said the car-wash requirement probably wouldn't be illegal if it weren't for the gasoline crisis. "If they were selling flour and requiring customers to buy sugar, it wouldn't matter," he said. "But it becomes illegal when the seller has sufficient market power with one product to force a customer to buy another product."

Ryffel, 19, said he understood why the attorney general was cracking down, but felt the suit rather silly. "We thought the $5 limit was sufficient to allow people who really needed gas to get some," he said.

The suit seeks no legal penalty, but asks that the car-wash requirement behalted and that Ryffel pay the attorney general's legal fees. Ryffel has 21 days to reply.