Ford Explorer complaints continue even after carbon monoxide leak repairs

The Center for Auto Safety is renewing its call for an immediate recall of the Ford Explorer, demanding Ford and the government take action on complaints about leaking carbon monoxide. The National Highway Traffic Safety Administration (NHTSA) has investigated the problem for two years. The number of complaints has grown into the thousands. At least 41 alleged injuries have been reported, but NHTSA has yet to publicly offer any answers.

Now at the two-year anniversary of the investigation, safety advocates are expressing frustration over the limited information coming out of NHTSA, reports CBS News correspondent Kris Van Cleave. Following our reports and the decision by a number of police departments to start parking Explorers, Ford began offering a free repair if a customer asks for it. The automaker claims it "effectively resolves" the problem.

NHTSA has since received almost 200 complaints about the issue. And we've found nearly 60 complaints to the regulator from drivers who say they had that fix and are still experiencing signs of exhaust or carbon monoxide seeping into the cabin of their Ford Explorer. We've also found complaints about the issue starting to show up in the 2018 Explorer as well.

One of those complaints, from a 2016 Explorer owner in Redding, California, reports "a rotten egg smell" when the SUV accelerates at a high speed with the EcoBoost in use. "I've taken it to Ford to have seals checked and the smell is still there," the owner said in the complaint. "My toddler complains of headaches every time we're in the vehicle and I've had nausea several times."

NHTSA expanded its investigation last year following our reports and now includes more than 1.3 million SUVs from model years 2011 to 2017, but not the 2018s. 

In a statement, Ford told CBS News: "Explorers are safe. Owner complaints to Ford and NHTSA have decreased since we announced our complimentary service for exhaust odor last fall as it effectively resolves the matter. If an owner continues to have concerns after the service is performed, they should contact their dealer for further inspection."

NHTSA told CBS News in a statement: "Safety drives everything we do at NHTSA. The agency's ongoing investigation includes testing multiple civilian and law enforcement vehicles; conducting field inspections of complaint vehicles and crashes involving police units, including those with aftermarket modifications; testing and monitoring Ford customer service repair campaigns for effectiveness and continuing to evaluate consumer complaints. NHTSA urges all consumers to schedule the repair with their dealers and to report potential safety issues on NHTSA.gov or by calling the agency's vehicle safety hotline at 1-888-327-4236."

NHTSA provided no timeline for the investigation's completion.