YOKOHAMA, Japan — In less than a year Nissan has lost its chairman to a financial misconduct scandal; its profits have plummeted; and its ties to Renault, often seen as crucial for its future, have fallen apart. And now, its embattled chief executive is leaving in the shadow of a pay scandal.

The departure of the executive, Hiroto Saikawa, follows months of speculation about his ability to manage the Japanese carmaker since it was rocked by the arrest last year of its former chairman Carlos Ghosn.

The resignation was announced less than a week after Mr. Saikawa said he had received payments from Nissan well beyond his earnings — an admission that echoed the charges that led to Mr. Ghosn’s fall.

[Nissan’s earnings reveal the long ahead for the company.]

“As the auto industry is facing a big transformation, the question is who should be running the company?” Nissan’s chairman, Yasushi Kimura, said at a hastily arranged news conference at Nissan’s headquarters in Yokohama. “Replacing the top executive of the company will enable it to be a leader in the auto industry.”