Diesel engines used by Jeep Grand Cherokee and Suzuki Vitara models sold in the EU used "prohibited emissions strategies" to emit more oxides of nitrogen (NOx) during regular road driving than during emissions testing, according to the RDW, the road authority for the Netherlands.
In a statement to Reuters, the RDW said Jeep has developed a software patch to the authority's satisfaction. The off-road brand will be ordered to recall affected Grand Cherokee models and apply the fix.
More ominously, the authority stated "Suzuki must come with adequate improvement measures or the RDW will begin the process of revoking its European type approval".
It has also begun the process of revoking type approval for the Grand Cherokee as a "precautionary measure".
At the time of publishing, Fiat Chrysler Australia was still waiting to hear back from headquarters about this issue, while Suzuki Australia has not yet responded to queries.
As the RDW is currently acting as the EU's reference regulator, any action it takes against these two vehicles applies across the entire European Union.
Stientje van Veldhoven, secretary for infrastructure the Netherlands, said the Dutch parliament will inform prosecutors of the RDW's findings.
This isn't the first time Fiat Chrysler (FCA) has been sanctioned by regulators over NOx emissions from its diesel engines. In early 2019, the automaker reached a deal with American authorities regarding 100,000 Jeep Grand Cherokees and Ram 1500 models fitted with the 3.0-litre V6 EcoDiesel engine.
As part of the settlement, the automaker agreed to fix the vehicles via a recall scheme, compensate owners, pay a fine, and contribute to California's pollution mitigation programs.
While the deal will cost FCA around US$800 million ($1.2 billion), the automaker is keen to point out there was "no finding or admission with regard to any alleged violations of vehicle emissions rules".