President-elect Jimmy Carter is giving "serious consideration" to setting up a toll-free phone line to the White House on which citizens could get help on their problems with the government, Carter's press secretary, Jody Powell, said today.

The "troubleshooter" line, modeled on a program Carter instituted with a federal grant while he was governor of Georgia, is a possible part of the new President's campaign to overcome the barriers between himself and other government officials.

Powell emphasized at a news briefing today that studies were just beginning on the cost and feasibility of the project and that no decision has been made. He said it was possible the troubleshooters might be located at the state level rather than in Washington.

Carter himself was secluded today with briefing books for the discussions he will hold here Thursday and Friday with his economic advisers and congressional leaders on the economic stimulus package he is expected to recommend to Congress before his inauguration Jan. 20.

His economic advisers will meet with him here on Thursday afternoon and the congressional leaders will join the discussions the next morning.

Powell declined to guarantee that the specifics of Carter's mixture of tax cut and job-creating programs will be decided in the two-day period. But he said, "The obvious purpose is to get agreement as far as possible across the board. Obviously the sooner we can get it done the better."

Meantime, Powell told reporters there had been an "overwhelmingly favorable" response from the public to Carter's invitation last week for suggestions on how he might escape from the "strange and unnatural world" of politicians, press and staff members that surrounds most Presidents.

Carter, through, powell, had asked people to send their suggestions to the transition team in Washington. Almost 3,000 letters and telegrams have been received, Powell said, with only a dozen expressing skepticism.

Among the suggestions that will be considered by a staff committee Powell is heading are:

Improving presidential communication with the public via fireside chats, radio call-in programs and "people's press conferences."

Inviting ordinary citizens to occasional lunches and dinners at the White House, setting up town meetings with the President and Vice President in local communities, and Sunday afternoon phone calls from the Carters and other administration officials to randomly selected families around the country.

Traveling with a smaller entourage, in ordinary cars, trains or planes, and eating in hamburger places and other run-of-the-mill restaurants.

The toll-free "action line," as used in Georgia, required about a dozen members of the Carter staff at a time working round-the-clock shifts to monitor the phone, Powell said. He said the phone monitors had instructions to stay on the line with each caller until an answer had been received from the appropriate agency or an agency the problem.