Sunday subway service, widespread use of "flexitime" working hours and mass "marshaling yards" in the suburbs where potential car pool partners can meet were among gasolinesaving suggestions proposed to Washington-area governments yesterday.

The Metropolitan Washington Council of Governments, a regional coalition of public officials, also asked the federal government to cut back on thousands of free and low-cost parking spaces for federal workers.

The proposals, drawn up by the COG staff, will be sent to local governments for discussion and suggestions. COG is trying to stimulate and coordinate conservation measures, but it is up to the local governments themselves to implement them.

Meanwhile yesterday, a representative of area service stations said that curtailments of gasoline supplies have now forced about half the area's 1,500 to 2,000 stations to close Sundays. Additional stations are trimming their hours of operation during the week.

Hundreds of station owners here whose gasoline supplies were sharply reduced under the federal allocation rules are having "serious problems meeting their rental payments" according to Vic Rasheed, head of the Greater Washington-Maryland Service Station Association.

But Rasheed also said that most dealers are "learning to work within the pattern" of reduced supplies and that motorists are not being severely affected.

"The motorist, all he has to do if he finds a station closed (is) find another that's open," Rasheed said. "This would be a good time for motorists to develop a source of supply and become known at a particular station."

In presenting COG's proposals yesterday, energy committee chairman Edward M. Steudel of Gaithersburg said the gasoline supply situation is "volatile and unpredictable" but does not yet constitute a crisis.

"We believe that these conservation measures will have sufficient payoff in terms of fuel savings that we can avoid major disruptions of life styles and economic activities," said Steudel, a Gaithersburg councilman.

But as soon as the assorted local politicians around the table -- the COG board members -- began discussing the proposals, it became clear that there will be disputes over many of the measures.

Martha Pennino, a Fairfax County supervisor, said that the proposal to eliminate free and low-cost parking causes "a terrible bind" in the suburbs where people must drive to work because public transportation doesn't serve them.

James McCoart, a Prince William County supervisor suggested that people be encouraged to limit their boat and other recreational gasoline usage -- but Pennino spoke up to say this might hurt the tourist industry.

She warned that some gasoline-saving measures could have "a disastrous effect on commerce."

McCoart suggested that people who drive alone to the Capital Centre should pay more to park than those who drive there in groups. Fairfax city council member Suzanne W. Max suggested that Metrobuses should be parked overnight at the end of their runs rather than "deadheading" back into town empty at night.

Measures included on the list of proposals to be sent to the local governments are:

Expand programs to encourage car pooling, which COG calls "ridesharing" and "ridematching."

Get civic associations to encourage people to combine nonwork auto trips. Nearly two-thirds of all auto trips are short hops to places such as the grocery store -- rides that waste gas since a car is most inefficient in its first few miles of operation.

Set up a reserve bus fleet for use in areas not normally served by buses.

Give preferential treatment to car and van pools in fringe parking areas.

Invoke commercial parking rates for government and private sector employes where subsidies exist.

Increase efficiency of government building energy use.

Increase efficiency of government car fleets. Tuning up all the cars in a fleet can result in a 5 percent gas saving, according to COG.