FILE – Plant employees drive 2011 Ford Explorer vehicles off the assembly line at Ford’s Chicago Assembly Plant in Chicago, Dec. 1, 2010. The U.S. government’s road safety agency has closed a more than six-year investigation into Ford Explorer exhaust odors, determining that the SUVs don’t emit high levels of carbon monoxide and don’t need to be recalled. (AP Photo/M. Spencer Green, File)

DETROIT (AP) — The U.S. government has closed a yearslong investigation into exhaust odors in Ford Explorer passenger cabins, determining that the SUVs don’t have high levels of carbon monoxide and don’t need to be recalled. The National Highway Traffic Safety Administration says it reviewed more than 6,500 consumer complaints and tested SUVs in the field. The probe covered nearly 1.5 million Explorers from the 2011 to 2017 model years and involved complaints of sickness and crashes that involved three deaths and 657 injuries. Many complaints came from police departments. But the agency said Monday that testing showed no Explorers that were sealed under a 2017 Ford service campaign had carbon monoxide levels higher than Environmental Protection Agency limits.