BECAUSE CONGRESS won't make up its collective mind on a director to run it, the Congressional Budget Office is now in some considerable danger. In the 13 years since it was established, the CBO has acquired a highly talented staff and a reputation for unbiased analysis. If that reputation is now eroded by continuing neglect on the part of the congressional leadership -- or, worse, by an overt attempt to make it more responsive to Democrats' day-to-day interests -- the quality of the staff and its research will inevitably decline.

The first victim would be Congress itself, for the kind of work that CBO does is a source of real power in the budget wars. There would no longer be an authoritative answer to the claims and charges made by the White House.

The last director of the CBO, Rudolf Penner, announced 14 months ago that he was leaving. After waiting four months for Congress to name a successor, he left. His deputy, Edward R. Gramlich, became acting director, but, last week, after another 10 months of procrastination by the congressional leaders, he returned to his teaching job at the University of Michigan. There are several well-qualified candidates for the job, but Congress would serve itself best by appointing Mr. Gramlich. He's a fine economist who has been running the agency with skill and balance.

But within the past month, the speaker of the House, Jim Wright, has begun to show an interest in the choice -- the wrong kind of interest. While simple indifference was earlier the reason for the delay, it now appears that a squabble has developed over Mr. Wright's insistence that he name his own candidate. Senate Democrats, not to mention House Republicans, have resisted and there, for the present, the decision is deadlocked.

It seems to be mainly an issue of personal prerogative. But there's an undercurrent of suspicion that Mr. Wright intends to turn the CBO into a more partisan operation. To do that would be to squander a great resource. CBO has given Congress, for the first time in this century, budget and economic information that is as good as the president's.

Sen. Lawton Chiles, the chairman of the Budget Committee, does not intend to pursue reelection. Perhaps he might consider, as an enduring service to Congress, taking an active role at last in resolving this standoff in a way that will be seen to preserve the CBO as an institution above political manipulation. It won't be easy. One of the peculiarities of the present leadership is that relations between House and Senate are more abrasive with both under Democratic majorities than when the Democrats held only one house and the Republicans the other.