Northern Virginia legislators are pressing for a review of car pool requirements on I-66 and traffic control plans for Shirley Highway.

Rep. Frank R. Wolf (R-Va.) has scheduled a public hearing for April 14 to consider the impact of car pool regulations on the recently opened 10-mile section of I-66 from the Capital Beltway to the Theodore Roosevelt Bridge.

Wolf already has suggested he may push for an easing of the rules, which restrict the road to four-member car pools and buses during rush hours.

In Richmond, state legislators from Alexandria and Fairfax County met with Virginia highway officials last week in an attempt to sidetrack plans for a $22.9 million traffic control system that includes signal lights at ramps leading to Shirley Highway (I-395).

Highway administrators refused to drop their plans but said they would consider possible changes in the system after it starts next summer.

State Sen. Wiley F. Mitchell Jr. (R-Alexandria), who arranged the meeting, asserted later that Alexandria, Fairfax and other Northern Virginia governments should challenge the state's plans in court.

Some Northern Virginia officials contend the ramp signals will cause delays for commuters and traffic backups in residential neighborhoods. Highway administrators-dispute these views.

The car pool requirements on I-66 stemmed from a prolonged battle over the road's construction that pitted highway officials against environmentalists and neighborhood groups. The restrictions were mandated in a 1977 decision by former U.S. secretary of transportation William T. Coleman Jr. and cannot be lifted without federal approval. But those who opposed the road in the first place predicted those restrictions would come under attack again shortly after the highway opened.

Under those regulations, from 6:30 to 9 a.m. on weekdays, eastbound traffic is limited to car pools and buses. The same restrictions apply to westbound traffic 3:30 and 6:30 p.m. Heavy-duty trucks -- those with two axles and six or more tires -- are barred at all times.

Wolf is considering proposing a relaxation of the rules to permit three-member car pools during rush hours, an aide said. Another possibility, the aide said, would be shortening the rush-hour periods during which the restrictions apply. For example, the aide said, the rules might be in effect only from 7 to 8:30 or 9 a.m. and from 4 of 4:30 to 6 p.m.

Highway officials argue, however, it is too soon to consider modifications of the rules. Traffic patterns normally take about a year to develop on new highways, they say. The final section of I-66, officially named the Custis Memorial Parkway, opened in December.

Among other issues expected to be raised at Wolf's April hearing on I-66 are complaints by motorcyclists and sports car owners, who are barred from the highway during rush hours because their vehicles cannot carry four riders.

The computerized traffic control system was scheduled to go into operation in the spring but has been delayed until June or July, officials say, because of unexpected difficulties in installing communications cables.

State highway officials say the system is designed to maintain an even flow of traffic and reduce accidents. Similar equipment is being installed on I-66, but the controversy has focused mainly on Shirley Highway.

Last week's Richmond meeting followed complaints by two Northern Virginia governments. In December, the Alexandria City Council passed a resolution opposing the ramp signals. Earlier this month, the Fairfax County Board of Supervisors adopted a resolution in which it "strongly questions" the plans.

Harold C. King, commissioner of the Virginia Department of Highways and Transportation, contended at last week's meeting that the traffic control system was properly designed. "He tried to reassure them of that," a spokesman said. "It's a good concept. We don't feel that the city's worst fears are going to materialize."

Suburban officials apparently were not persuaded. "It's going to be so bad that they should change it before they test it," said Alexandria transportation director Dayton L. Cook.