Upmarket German carmaker Audi on Tuesday abandoned attempts to find an investor for its plant in Brussels, which it plans to shut down in February amid major cutbacks in its parent company, the Volkswagen Group. “The potential investor from the utility vehicle sector has withdrawn its indication of interest,” Audi said from its Ingolstadt headquarters in Bavaria. “There is no potential investor for the production site, and so the active search for an investor has been concluded,” it said. Audi has been negotiating with the works council and trade unions for the past four months on a social pla…