NEW YORK — Stellantis CEO Carlos Tavares is stepping down after nearly four years in the top spot of the automaker, which owns car brands like Jeep and Ram, amid an ongoing struggle with slumping sales. The world’s fourth-largest carmaker announced that its board accepted Tavares’ resignation on Sunday. He will leave his role as chief executive immediately. Stellantis noted Sunday that the process to appoint a new, permanent CEO is “well under way.” In the meantime, the company says a new interim executive committee, led by chairman John Elkann, will be established. As head of PSA Peugeot, Tavares took control of the Netherlands-based company in January 2021 — when it merged with Fiat Chrysler Automobiles.