Sunset legislation was widely endorsed by candidates in the 1970s, eager to show they intended to get a handle on out-of-control government programs, agencies and spending.

But then the sunset laws, which require a periodic review of programs and agencies with an eye to ending those that have outlived their usefulness, stalled in Congress.

Like recent demands for a constitutional amendment to balance the budget, the sunset process was easier said than done and the concept looked better in the abstract than in the cold light of reality.

So, although President Carter, 87 senators and 200 House members have endorsed sunset, it languished almost four years.

Now sunset legislation is moving again and is likely to be voted on in both chambers early next year. But the revived versions are not likely to present the sudden-death threat to programs that the original concept envisioned.

As originally proposed by Sen. Edmund S. Muskie (D.-Maine) in 1976, sunset would have required Congress to review all federal programs every four years. Unless Congress specificaly authorized a program it would automatically terminate.

But a bill the House Rules Committee is working on would remove the mandatory review and automatic termination features. And a group of senators, headed by Sen. Jacob Javits (R-N.Y.) is attempting to amend Muskie's bill to stretch out the review requirements and give committees more flexibility in what they would review.

Rep. Gillis Long (D-La.), whose Rules subcommittee has worked on sunset more than a year, has written the new House bill. It has gained support of younger members such as Reps. Leon Panetta (D-Calif.), Butler Derrick (D-S.C.) and Richard Gephardt (D-Mo.)

"In a perfect world, I would like to see it strengthened," Gephardt said, adding he would like to see sanctions against a committee if it did not perform the reviews it was supposed to. But Geophardt said it might be difficult to get the Long bill passed, "caught as it is between those who want the original sunset bill (Muskie's S.2) and those who think the whole idea is unnecessary."

Long was apprised of the reasons for opposition when he sent questionnaires to committee chairmen who would have to make sunset work.

The chairmen, who had been relatively silent, wrote that sunset would add a terrific burden to their workload, require more staff and could become an automatic gesture, that is, another reform that did not change anything.

"A systemized approach to oversight would lead to a systemized response: pro forma reauthorization and reexamination having little or no effect on programs of policies," Government Operation Committee chairman Jack Brooks (D-Tex.) wrote. Under the gun of a deadline for trying to look at every program. "There would be less objective program evaluation than the present reauthorization process provides," Brooks said.

Another problem was commented on less openly but was a worry for the chairmen: If a minority on a committee wanted to kill a program, it could simply withhold a quorum and prevent the panel from acting on an authorization until the deadline passed and the program was automatically terminated.

Finally, as sunset moved beyond the slogan stage, interest groups began to back away or ask for exemptions.

For example, when tax expenditures -- tax deductions or credits generally given to business -- were included as an item for periodic review, the Chamber of Commerce lost its enthusiasm for sunset. The chamber worried that uncertainty about whether a tax expenditure would be killed or not would lead to instability in the business community.

Labor feared social programs would be prime targets for termination. Pensioners and other recipients of government benefits wanted exemptions from automatic termination too.

"Each group can make a legitimate case for exemptions from automatic termination," Long said, "but the end result . . . is a list of exemptions that rival the inclusions."

Under Long's version of the bill there would be an inventory of all programs, lining them up with the various committees (sometimes two or three) which have jurisfiction over them.

Committees would then have to coordinate and adopt review agendas by March 1 of a new Congress, telling which tax expenditure or programs they intended to review. Unless it reported an agenda, a committee could not get money to operate from the House Administration Committee.

A consolidated agenda, listing all committee agendas, would be adopted by each body.

By May 15 of the seacond year of a congress, comittees would make recommendations to reauthorize, modify or kill a program. But extinction of a program would not be automatic if the deadline, was missed and no sanctions of the type Gephardt wants would be levied on a committee.

If a committee did recommend ending a program, both houses would have to approve.

In the Senate the new proposal by Javits supported by Sens. Charles Percy (R-Ill.) and Abraham Ribicoff (D-Conn.), would allow committees to suggest programs they wanted to review.

The Senate would consider their recommendations when debating the budget resolution in even-numbered years. The committees would have two years to evaluate programs and introduce reauthorization. Programs not reauthorized would die.

To some in the Senate, where the sunset idea is stronger, the proposals are too weak.

"I think it seriously dilutes the sunset concept," Sen. Jim Sasser (D-Tenn.), a Muskie bill supporter said. "Unless something is mandated, inertia will take over. "To say this is too much of a burden on Congress "is really an admission that government is so large nobody can get a handle on it. That's what S.2 is all about."

Sasser will fight the Javits proposal when the Government Affairs Committee begins discussing sunset this week. He is "very optimistic" the committee will keep the Muskie proposal intact.

But even if it does, the House clearly is headed toward a less-strict approach, and the final product is likely to be more flexible than the Muskie bill.

"The surest path for improved oversight is to create incentive for committees to incorporate review into their regular legislative activities," Long said. "Committees must be willing to conduct the reviews or they won't be done."

Rules Committee Chairman Richard Bolling (D-Mo.) said, "I've seen a lot of sanctions imposed in my 30 years in Congress. And I've seen a lot of them observed to the breach."