The Washington Post area's bus and subway system returned to nearly normal service yesterday, although key issues in the bitter labor dispute remained unresolved.

Bus drivers expressed mixed views about what they believed had been the chief effects of their illegal weeklong strike, although a number of them voiced disappointment because they had lost several days' wages and apparently gained relatively little.

"As far as I'm concerned, it was just three lost days," one driver said yesterday.

Steps are under way by Metro, union and other officials to seek a rapid settlement of two issues that emerged as central points in the crippling strike. As arbitration hearing is scheduled for today to consider whether Metro employes are due an immediated 20-cents-an-hour, cost-of-living increase, one of the strikers' claims. A decision is required by Aug. 6 under a federal court order.

In addition, Metro officials have begun weighing possible disciplinary measures against some participants in the work stoppage, strikers have demanded a blanket amnesty. Metro general manager Theodore C. Lutz, reasserting the transit authority's previous stand, said last night that amnesty was "not appropriate." Metro officials estimated yesterday that about 250 employes would be interviewed by their supervisors to determine whether disciplinary proceedings should be instituted against them.

Considerable friction developed yesterday over some of Metro's initial disciplinary actions, as union leaders and some Metro employes angrily complained about what they viewed as unduly harsh measures. The transit agency later, as one key official put it, "reinstructed" its supervisor officials, ordering them to limit disciplinary proceedings to employes who has actively participated in the strike, such as those who picketed or sought to intimidate other workers.

Metro officials reported that only 13 of the 1, 567 buses that normally are on the streets during the morning rush-hour period had failed to go out yesterday. All 13 drivers who has not shown up are employed at the bus system's big Blandensburg Division garage in Northeast Washington - one sire of considerable labor unrest - but Metro officials said they were uncertain whether the drivers' absence was linked to the wildcat walkout, which ended on Tuesday.

Bus service during the afternoon rush hours was reported to be normal.Subway operations continued without any significant breakdowns or labor disruption throughout the day, as they have since Monday morning.

Slightly fewer passengers boarded Metrobuses yesterday than on a normal summer day, Metro officials said, apparently because of lingering uncertainties about whether bus service would remain uninterrupted. A spokeswoman for Metro said the decrease in normal ridership yesterday appeared to have been about 10 per cent.

At the same time, city transportation officials said that slightly more commuters had continued to drive to work by car yesterday than on typical simmer day. Seward E. Cross, the District of Columbia's deputy traffic engineering and operations director, said above-normal traffic was most evident on New York Avenue, East Capitol Street and bridges connecting Virginia with the District.

Neither Metro hor union officials, who did not sanction the wildcat strike, would flatly rule out the possibility of another such walkout in the future, although they appeared to express guarded optimism. This month's transit disruption was the second since May. A wildcat strike on May 18 was touched off by the rape of a female bus driver and was aimed at getting increased security aboard Metrobuses.

Metro general manager Lutz said he believed that this month's strike has resulted in greater awareness among Metro employes of their rights through arbitration and other legal avenues. "I hope that broader understanding is helpful. I'm not very good at predicting," Lutz said in a telephone interview.

How significantly the two wildcat protests have undercut the authority of the transit workers' main labor group, Local 689 of the Amalgamated Transit Union, also remains unclear.

"There are going to have to be some changes made," George R. Davis Jr., the local's president, said in a telephone interview, adding that the union needs to establish "better lines of communication" with its members. Davis also expressed uncertainty about whether he would seek reelection as local president next year.

Although Metro appeared to have withstood the strike without offering major concessions, some strikers and one of their lawyers said they believed that some gains had been achieved. Lawrence Speiser, a lawyer for the strikers, noted that arbitration over the cost-of-living dispute had been accelerated as a result of the walkout and that Metro had backed away from some of its initial threats to suspend striking employes.

"There were things that were accomplished," he said.

A number of drivers, who were interviewed outside the Bladensburg Divulsion garage yesterday afternoon, translated their feelings into dollars and cents.

"I'm glad to be back," said LeRoy Newsome, who has driven a bus for five years. "You have your rent to pay, food bills." He said he had lost more than $300 in wages and overtime during the walkout, although he believes the walkout will force Metro to pay cost-of-living increases.

"I came back disappointed because we didn't really accomplish too much," said another driver, Gregory Curry. "Financially, it hurts." He counted his losses at $180. Nevertheless, he added, "It proved that we could all stick together."