The 96th Congress, which has werestled itself into a corner with its slow pace, returns Wednesday from its August recess still facing the most controversial issues of the year.

At the top of the list are President Carter's multi-part energy package, the strategic arms limitation treaty and the fiscal 1980 budget.

In addition, Congress must confront everything from Chrysler's bid for federal aid and the resettlement of Indochinese refugees to the reinstitution of the draft.

Meanwhile, Carter's cabinet reshuffling requires a new set of confirmation hearings, at least one of which -- for HUD Secretary-designate Moon Landrieu -- will be sticky.

An October adjournment date, longed for by the leadership, is out of the question. This is a Congress that will be pushing hard to finish by Christmas.

The pace so far has been exceedingly slow. Only a few major pieces of legislation have cleared Congress. Almost all are in the area of foreign affairs, including a new international trade agreement act, funding of the Israeli-Egyptian peace treaty and setting up a new nongovernmental relationship with Taiwan.

What began as a year of austerity has turned into a year of agonizing. "There's nothing but thorns on the bush, and nobdody's in a hurry to hand out thorns," one congressional aid said.

Carter's failing fortunes have added to Congress' doubts and questioning, particularly of his energy programs.

Just before the August recess, the House gave Carter gas rationing authority, but insisted it could only be invoked if a 20 percent oil shortage had developed. It also gave him other conservation authority but only if the shortage was 10 percent for a month or more.

To further confirm its distrust, the House demanded the right of a congressional veto of any conservation or rationing plan the administration produced.

In the same bill, it created a loophole in the one conservation measure it already had passed a requirement that the thermostats be set at 78 degrees in summer and 65 in winter in public buildings. The loophole exempts businesses that can show comparable savings through other methods.

The administration considers the House-passed requirements odious, and is asking the Senate to keep them out of its version of the energy conservation bill. But some form of a trigger -- a minimum oil shortage before Carter can exercise conservation authority -- and one House veto may be necessary for the bill to clear the House in its final form.

Meanwhile, the Senate Finance Committee, headed by Russell Long (D-La.), gets its crack at a windfall oil profits tax and is expected to water down the House-passed tax that is expected to raise $142 billion by 1990. Carter said planned changes could rob the ill of $54 billion. Still to be considered are plow back provisions returning money to oil companies if they invest in exploration.

Carter wants the windfall tax in part to pay for a new program to develop synthetic fuels. But while Carter wanted $88 billion authorized at once, a Senate panel scaled that down to $20 billion.

Legislation to cut red tape on new energy projects has cleared two House committees and is well along in the Senate committee. But legislation faces a big floor fight in the House on whether to waive federal, state and local laws, a move opponents say could give unlimited powers to the president and the energy mobilization board the bill would set up.

Battles over further distribution of the energy trust fund that would be set up by the proposed windfall profits tax have not yet begun. Money for the poor, for mass transit and for various other interests all are expected to come out of the fund.

Prospects for ratification of the strategy arms limitation treaty with Russia are improving in the Senate, but the announcement that the Soviets have 2,000-3,000 combat troops in Cuba may give opponents a new weapon. Floor debate could take at least a month.

Meanwhile, the treaties turning over the Panama Canal to Panama are scheduled to take effect Oct. 1. Legislation implementing those treaties is tied up in a House-Senate conference. At issue are conditions attached in the House that the administration considers too restrictive.

In one bright spot, Congress has given Carter at least until Nov. 15 to decide whether to lift economic sanctions against Zimbabwe-Rhodesia. If he decides to keep sanctions on after that date, Congress could take action on its own to lift them.

On the economic front, Congress returns to face a new budget battle. Automatic spending increases for several programs threaten to enlarge the budget deficit approved in May. Sen. Edmund S. Muskie (D-Maine) is asking the Senate to cut $4 billion in spending that seven committees already have approved, a move expected to provoke a major fight. The House has not yet taken up the budget problem.

Congress and the administration are studying ways to help the faltering Chrysler Corp. without giving it a tax break or waiving deadlines to meet emission and mileage standards. A loan guarantee is a possible solution, although even that route would be controversial.

A battle over draft registration will come up soon in the House when it takes up a $42 billion defense authorization bill. The Armed Services Committee bill would require the president to begin registration under the Selective Service System of 18-year-olds on Jan. 1, 1981. Opponents will try to knock out the draft provision when it comes to the floor.

The House Ways and Means Committee has passed a hospital cost containment bill to keep hospital costs from rising more than 11.6 percent over last year's costs, but the bill still faces a tough fight on both the House and Senate floors.

A bill setting up a separate department of education passed the House and Senate, but the House passed it by only four votes, and only after attaching several controversial amendments. House opponents still hope to defeat the measure.

A controversial sugar price support bill also is headed for the House floor, with consumer groups gearing up to fight it. The bill uses import fees and quotas to boost the price of cheap foreign sugar to 15.8 cents a pound, and givea a one-half cent a pound payment to domestic producers.

A bill that would restore about half of the routes eliminated by Amtrack passenger trains faces action in the Senate.

Both Houses also must complete action on major spending bills, including increases in defense appropriations that Carter may request to help SALT through the Senate.