In 2016, the National Highway Traffic Safety Administration (NHTSA) launched an investigation into 2011-2017 model year Ford Explorers after thousands of instances of police departments reporting an intrusion of exhaust gasses into the cabin. In some cases, the issue was so bad that officers alleged that they had been incapacitated while behind the wheel. However, the agency has finally wrapped up its probe, deciding that the manufacturer wasn’t at fault.

So then, what exactly did happen?

With over 6,000 complaints of exhaust odors leaking into the vehicles – including a sizable number of extreme cases involving the Police Interceptor variant of the Ford Explorer – it seems unlikely that the problem was imagined. Some of the complaints were even accompanied by crashes, with the affected drivers stating that they were overwhelmed by exhaust fumes and lost consciousness.

But the NHTSA closed its investigation on Monday, opting against any recalls. The investigation took over six years and encompassed 1.5 million vehicles, with the agency ultimately deciding that elevated levels of carbon monoxide probably weren’t the fault of the original manufacturer. Instead, the NHTSA suggested that the problem likely stemmed from modifications made to the vehicles – which is also what Ford said when the fingers first started being pointed.

According to Reuters, the agency explained: “that the 2011-2017 Ford Explorer vehicles when accurately measured produce occupant compartment (carbon monoxide) levels which fall below current accepted health standards.”

However, groups upfitting the Police Interceptor Utility variants are presumed to have screwed up in some instances – likely allowing exhaust gasses to leak into the vehicle. Government fleets often undergo heavy modifications, especially vehicles designated for police use. While Ford does a lot of this in-house, departments often add their preferred light bars, cages, computers, and power systems necessary to run all the things normal Explorers don’t have afterward. The NHTSA believes shoddy workmanship left some fleet vehicles with holes that allowed exhaust fumes into the cabin.

"Sealing issues caused by upfitting were responsible for the highest measured Carbon Monoxide Levels in tested vehicles," explained the agency.

Additionally, the NHTSA stated Explorers that had received damage (especially standard models that weren’t designated for police use) as having the highest carbon monoxide levels witnessed during testing. 

Considering the above, regulators opted against forcing a recall. However, Ford has already been fixing these vehicles via a Field Service Action. In 2017, Blue Oval agreed to cover the costs of specific repairs in Police Interceptor SUVs that it previously alleged were tied to aftermarket installations of police equipment. This led to a lot of speculation that Ford was attempting to cover its rear end by shifting the blame while also conducting repairs. But, with the NHTSA, backing up its original claims, the automaker appears to have been vindicated.

On Monday, Ford said it was pleased with the results and that its own internal "investigation and extensive testing determined the same results, which we have always maintained."

[Image: Glenn Highcove/Shutterstock]

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