Motorists in Washington and Maryland will find the cost of a fill-up a little higher today as new gasoline taxes of 2 cents a gallon go into effect in both jurisdictions.

There is some good news for motorists with a sweet tooth, however: An 8 percent candy tax levied in the District since 1980 is abolished as of today.

The gasoline tax increase in Maryland, from 9 cents to 11 cents a gallon, is part of a multimillion-dollar program to build and repair Maryland highways over the next two years.

Under the program, approved by the legislature this year at the urging of Gov. Harry Hughes, taxes will rise another 2 1/2 cents per gallon next year. After that, the tax will automatically rise one cent each year, providing wholesale prices are above a certain threshold.

The District tax is scheduled to rise from 11 cents to 13 cents a gallon. The city also has a system for automatic future increases, based on the Washington consumer price index of the previous two years.

In April this year, Mayor Marion Barry asked the City Council to put off today's increase, contending that higher-than-forecast gasoline sales indicated the current rate would raise enough money for the budget without the additional tax, which is expected to bring in an additional $2 million over the next year and a half.

However, the council, which rejected a similar request from Barry last year, allowed the increase to remain. The request marked the third time that Barry had asked for a repeal or reduction of a gasoline tax that his administration had initially supported.

Barry's press spokesman, Annette Samuels, said yesterday that Barry "sought to get the council to block it and the council didn't see fit to do it. He did his part."

John A. Wilson (D-Ward 2), chairman of the council's finance and revenue committee that did not act on Barry's request, could not be reached for comment yesterday, but council members have indicated that they believe the city, even with the increase, is competitive with the surrounding jurisdictions.

The District's tax will be one cent below Northern Virginia's until July 1, when the levy there is scheduled to rise from about 14 cents per gallon to about 17 cents, based on combined state and local taxes and a new surcharge.

In repealing the District's 8 percent tax on most sugar items--soft drinks, candy, chewing gum and other confections--city officials acknowledged that merchants and tax collectors had difficulty enforcing it because of confusion about what food items containing sugar were exempt. Food in the District is generally exempt from sales taxes.

The council voted on Feb. 23 to repeal the levy.