Citing such current concerns as the need to save gasoline, reduce pollution and curb psychological stress, the D.C. Police Department renewed yesterday an order for a crackdown on motorists and bus drivers who obstruct interseections.

Police Chief Maurice J. Cullinane issued an order reminding officers of the regulation forbidding drivers to enter an intersection unless their vehicles can be accommodated on the other side without blocking pedestrians or cross traffic.

Metrobusses and intercity buses will be among the "main targets" of the enforcement drive, Cullinane said.

Although there have been previous occasions on which drivers have been reminded of the need to obey the regulation and police have been reminded of the obligation to enforce it. Cullinane said, "It is once again observed that an increasingly large number of motorists" are violating it.

Noting that violations generally occur during congested, rush-hour periods, the chief said they increase traffic hazards, cause traffic jams and impede traffic flow in all directions.

Furthermore, he asserted, there is a "loss of energy . . . from idling vehicles, plus a pollution of the air."

Cullinane issued the order after discussions with Deputy Chief Ernest J. Prete, head of the traffic division, who said the long delays caused by blocked intersections often leave commuters upset, irritable and unable to work properly.

"Strict enforcement" of the rule against blocking intersections was pledged as long ago as 1954 when a congressman described it as one of the best ways to ease traffic congestion.

In 1973, the City Council revised what was called in a news account the "seldom-used" regulation to reduce the amount of paperwork involved in issuing tickets, and hence ease enforcement.

However, Prete said yesterday that although blocked intersections "shouldn't happen," they have again become the source of numerous complaints. "We're going to crack down," he said.

A ticket calls for the posting of $15 collateral, according to police. Cullinane said police patrol units will be required to report monthly on their enforcement efforts.