House and Senate Republican leaders signaled President Reagan yesterday that Congress is likely to brush aside much of his campaign-year legislative wish list as it rushes to pass essential spending bills and go home to campaign early next month.

The leaders indicated that among the president's pet projects likely to be sidetracked are school prayer, tuition tax credits, a balanced-budget constitutional amendment, crime control legislation and anti-abortion legislation, which was tabled in the Senate yesterday.

"Presidents are like senators; they ask for more than they are going to get," said Senate Majority Leader Howard H. Baker Jr. (R-Tenn.), who joined House Minority Leader Robert H. Michel (R-Ill.) in suggesting that Congress may do little more than pass "must" legislation to continue the government's borrowing and spending authority before Congress recesses in early October.

Even then, there is a "substantial prospect" that Congress will have to return after the Nov. 2 general election to continue work on appropriations for the fiscal year that starts Oct. 1, said Baker, who opposes such a "lame-duck" session but says he feels it may be necessary.

One reason, he indicated, is pressure from appropriations committees for a relatively short-term continuing resolution that would maintain pressure on Congress to pass regular appropriations bills.

Baker met with House Speaker Thomas P. (Tip) O'Neill Jr. (D-Mass.) on the issue of a post-election session yesterday and is to consult further with other leaders before the issue is resolved.

Although some of Reagan's favorite campaign issues may be relegated to the congressional dustbin, he appeared likely to get at least one appropriations bill from the Democratic-controlled House that he can sign.

The House yesterday approved, 343 to 38, a $47 billion spending bill for the Department of Housing and Urban Development and 17 independent agencies. Republicans said Reagan would sign the measure on the understanding that it would fall within congressional budget ceilings.

Before that vote, the House approved, 200 to 184, a rider that would block federal enforcement of auto inspection and maintenance programs required under the Clean Air Act. The District of Columbia and its Virginia suburbs require auto emission inspections, while Maryland has delayed implementing such a program. On a voice vote, it blocked relaxation of carbon monoxide health standards.

The overall bill does not include money for new subsidized housing projects because authorization levels have not been set. It was agreed on the House floor that any spending over budget targets for projects included in the bill will be offset later by comparable reductions in spending for housing.

As approved, the bill exceeded Reagan's spending targets by $352.5 million but would restrict housing programs to no more than $9.6 billion in order to meet the budget target of $56.6 billion.

With that understanding, "We will have a presidential signature on this one," said Rep. Silvio O. Conte (Mass.), ranking Republican on the House Appropriations Committee.

The bill included more money than Reagan requested for operating existing housing projects and for the Environmental Protection Agency, as well as many smaller programs.

But the White House, burned last week when Congress overrode Reagan's veto of a supplemental appropriations bill that fell within budget ceilings accepted by Congress and the administration, has indicated it will not object to fiscal 1983 spending bills that meet budget targets.

A dispute continued yesterday, however, between the Pentagon and the Senate Appropriations Committee about cuts in the administration's big military buildup effort approved earlier by Congress in its budget.

Sen. Ted Stevens (R-Alaska) served notice late yesterday that the defense appropriations subcommittee, which he heads, will not mark up a defense money bill until an agreement can be reached with the Pentagon on spending levels.

The Republican leaders, after a half-hour meeting with Reagan, did not rule out action on so-called "social issues" such as abortion, prayer and tuition tax credits -- all backed by Reagan -- but indicated strongly that those issues are likely to be pushed aside for money bills that must be passed by Oct. 1 to keep the government operating without disruption.

Moreover, if Congress returns for a post-election session, money bills are again expected to dominate, Baker said. Although Senate Finance Committee Chairman Robert J. Dole (R-Kan.) has been pushing for a special session on Social Security financing reforms, neither Baker nor Michel indicated that they favor debating Social Security in a post-election session.

In the few days remaining before Congress is to quit in early October for the elections, Michel said he expects approval of no more than four or five appropriations bills, meaning a "bitter contest" is likely on spending levels for the continuing resolution.

In addition to House-Senate differences about spending, many lawmakers believe a presidential veto of the continuing resolution is possible, especially if Congress provides less for defense and more for social programs than Reagan wants.