Once upon a time, when gas was 35 cents a gallon and service stations vied for customer patronage, pump jockeys automatically washed car windshields and checked the oil.

Today, as people line up to pump their own gas, asking an attendant to look under the hood can be like asking a Boy Scout to rob a bank.

As a result, an increasing number of car owners are learning how to perform their own routine maintenance chores, and enrollment in basic car care classes is booming.

"The evolution of the self-service station has probably taken my place as a service-station owner when it comes to daily, routine maintenance chores," says Gene Buckley, a Wilmington, Del., service station owner and eastern area ARCO dealer representative who was in Washington to teach a short course in car care.

The course, co-sponsored by the League of Women Voters, was given to about 150 people, many of whom had trouble distinguishing between a fan belt and a dipstick.

"People looking for economy want to purchase their gas at the lowest possible price, which is often at the self-serve pumps," says Buckley. "This means drivers who didn't even know how to open their hoods are now getting into basic car care."

"With prices going up, (gas station) dealers are getting a lot of guff," says Julie Barker Middleton; consumer affairs director for Atlantic Richfield. "If you're going to survive in today's business climate you have to return something to the consumer."

To regain their customer's good will, the oil company began offering free car-care classes at several California ARCO dealerships last year. Each service station owner taught basic maintenance to a handful of local car owners.

The classes went nationwide in July 1978.Roughly 8,000 people, 90 percent of them women, have now taken the course, and Atlantic Richfield will spend half a million dollars on the program in 1979. Maryland ARCO dealers expect to begin offering the class next spring.

Washington area adult education centers also have noted a surge of interest in automotive maintenance classes.

"Five years ago we offered one class with about 10 to 15 students," said Morris Newcomb, Fairfax County schools' curriculum specialist for trade and industrial education. "This fall we're offering 27 classes in consumer car repair and service with about 15 to 20 students in each class.

"It comes out of necessity. Number one is inflation. People want to save money by doing their own maintenance and repairs. Number two is that gas stations are no longer doing the routine checking, and if you don't check it yourself, it might lead to costly major repairs."

The adult education departments of many area school systems and colleges offer low-cost courses in everything from "automobile maintenance for the notice" to special classes in tune-ups, brake repair and "Know Your Toyota" (or VW, Datsun, etc.).

For more information about ARCO's Car Care program, write the Maryland League of Women Voters, attention Mary Ann Burke, 5 State Circle, Annapolis, Md. 21401.