Large numbers of Washington area service stations are violating U.S. price regualtions and overcharging for gasoline.

Of 66 stations checked by The Washington Post over the past few days, 27 -- or 41 percent -- were charging more than allowed by federal law at least one full-service pump. The amount of the ovrcharge ranged from .1 to 5.7 cents a gallon.

At least six dealers rolled back prices to legal levels following a reporter's visit. Two of them immediately dismantled their pumps and changed the dials on the spot.

U.S. Energy Department auditors has previously found two of the 66 stations to be in violation of the law and had ordered them to roll back their prices.

On Aug. 1, the Energy Department simplified its complex gasoline price regulations for most dealers, allowing them a straight 15.4-cent margin on top of taxes and their "tankwagon prices" -- what they pay their suppliers for gas. On Dec. 15, the allowable margin will increase to 16. 1 cents.

Since the new regualtions took effect, most violations amount to only a few cents per gallon; previously, overcharges of 25-to-30 cents a gallon were not unheard of.

Because tankwagon prices can vary so much from oil company to oil company, it is difficuit for motorists to known whether they are being over charged by service stations. In addition, local and federal gasoline taxes vary among jurisdictions: 13 cents a gallon in Maryland and Virginia and 14 cents in the District of Columbia.

The Energy Department itself has audited 250 of the approximately 1,500 stations in the Washington area in recent months and found that 43 of them -- or 17 percent -- were overcharging.

These dealers all signed documents promising to roll back their prices, said Bart Isenberg, assistant administrator for enforcement in the departsment's regulatory arm. Some were fined$100 to $500 of a maximum possible fine of $2,500 per violation. The highest overcharge auditors found in this area was 8 cents a gallon.

The Lundberg Letter, a respected gasoline retailing newsletter, estimates, however, that 40 percent of full-service retail gasoline prices in the nation are over the legal limit, an estimate closer to The Post's finding.

According to Lundberg, "the high rate of apparent over-ceiling pricing suggests that federal ceiling regulations are, as a practical matter, largely unenforceable" -- meaning that the limited number of Energy Department auditing teams is simply incapable of keeping tabs on the nation's 250,000 service stations on a day-by-day basis.

Local dealers gave a variety of reasons when their overcharges were pointed out by a reporter.

"It's frozen," said Arlington Sunoco dealer Paul Buckler of the price dial on his unleaded pump, which was overcahrging by .7 cent a gallon. "Can't move the damn thing. We've been squirting oil on it."

However, an attendant at the station, located at 3212 Lee Hwy., was able to remove the pump's metal casing and change the dial to the legal level while a reporter watched.

"I pass my rent through, phooey on the government," said Rockville Texaco dealer John T. Dodson, who was overcharging 2.2 cents a gallon on regular and .4 cent on unleaded.

Dodson, whose station is located at 369 Hungerford Dr., complained that his rent is soaring and he cannot legally pass through this cost under federal rules.

"Them fellers is ripping us off, won't let us get any money," Dodson said of the Energy Department auditors. Neverthless, he rolled back his prices after a reporter's visit.

Gulf dealer Woodrow Royce, who operates a station at 4885 MacArthur Blvd. in the District of Columbia, said it was "an honest mistake" that his prices were higher than the legal level -- by 1.9 cents on regular, 2.9 on unleaded and 2.4 on premium. He rolled them back.

"My gas pump does not pay my overhead," Royce said. "For the hours I put in and the headaches I have, it ain't enough."

Royce was cited by federal auditors for overpricing two months ago and ordered to roll back prices then, which he did at that time.

Rector A. Sisk, a temple Hills, Md. Shell dealer whose prices were high by 2.1 cents on regular, 1.1 cents on unleaded and 2.1 cents on premium unlead, said the overcharges resulted from confusion in setting dials on pumps that register half the price to be paid per gallon.

"When they call and say gas is going up, (an attendant) goes out to raise the price," said Sisk. "He just forgot it was half price."

Sisk, whose station is located at 3301 Brinkley Rd., said his is "a neighborhood-type station and I sure don't want to rip anybody off." He rolled back his prices.

Arlington Gulf dealer Paul A. Nicolet said it was "entirely possible" that his prices were high by "a few tenths of a cent."

They were high by .7 cent on regular, .3 cent on unleaded and .2 cent on premium. Nicolet, whose station is at 2410 Lee Hwy., said he was cited for overpricing by DOE "a couple or three months ago -- I roled it back -- it was within tenths then, too."

According to Niclet, "It's a tad unfair to single out the dealers. My rent goes up Feb. 1 almost $6,000. You explain to me how I will survive this coming year. I'm just a small station."

Nicolet later called to say his prices had, in fact, been high and that he had rolled them back.

A dealer is not allowed to be higher than the legal price on one pump even though he may be lower on his other pumps -- generally the self-service pumps.

Exceptions to the rules are provided for stations operated by big oil companies and others who obtain special waivers from the Energy Department. But the rules hold for most dealers who least their stations from a big oil company and purchase all their product from that firm.

Isenberg said that motorists who suspect that stations are overpricing or who have questions may call the department's enforcement hotline, 254-5474 for the Washington area.