President Carter yesterday asked Congress to create an "Agency for Consumer Advocacy," within hours in a closely coordinated display of enthusiasm, bills were introduced in the House and the Senate to do just that.

In a special message to Congress, Carter endorsed a package for four consumer proposals, including essentially the same Consumer Protection Agency which Congress passed in 1975 but never sent to the White House because of a promised veto by then-President Ford.

Yesterday's actions mean consumer groups stand a good chance of getting an agency they've lobbied for eight years. The new bills are almost identical to the 1975 versions. Senate aides rate their chance of passage by both houses as excellent.

Presidential aide Simon Lazarus said the President's proposals are "substantially or completely met by provisions which appear in one or the other of those bills."

Both congressional bills would appropriate $15 million for an agency charged with advocating the views of consumers before other federal agencies.

It could, for example, urge the Federal Communications Commission to set telephone rates that benefit consumers, take a position on whether the Food and Drug Administration should ban saccharin, and advise the State Department and the White House about such actions as coffee agreements or shoe tariffs that might help hold prices down, or lobby for or against grain sales to foreign countries.

It could also take another agency to court if it thought a given decision ignored consumer views. Whether it would do those things or not would depend largely on whom Carter appointed to head the agency.

White House consumer affairs adviser Esther Peterson said the agancy would listen to consumers, but would make its own decisions about what actions to take.

An aide to Rep. Benjamin Rosenthal (D-N.Y.) author of the House bill, said it contains an exclusion preventing the consumer agency from intervening in Agriculture Department decisions on farm subsidies. The Senate bill, an aide said, contains no agricultural exclusions.

Carter's message also urged Congress to pass legislation giving citizens more of a right to sue the government, more chances to file class actions suits, and more help in making their views known to federal agencies and in court suits.

"As the federal government has grown, individual citizens have found it harder to learn how and where and when to go to influence the many government decisions which make a difference in their lives," the President said in his message.

"These measures - and the others which members of my administration will discuss in the months ahead - will enhance the consumer's influence within the government without creating another unwiedly bureaucracy," he said.

Peterson said the Office of Managament and Budget would decide what specific consumer-oriented activities now being performed by various agencies would be transferred into the new agency

Rosenthal told a news conference it may be necessary to keep some of the consumer coordinator offices that President Ford set up in 17 agencies as an alternative to an independent Consumer Protection Agency.

Joan Braden, whom Ford named consumer coordinator at the State Department, said yesterday she thinks both an independent agency and the consumer coordinators are necessary.