The German government found the emissions discrepancies after a broad range of tests were ordered following the Volkswagen diesel emissions scandal. While many vehicles were found to be polluting too much, the testing found that none of the companies were using a defeat device, meant specifically to trick emissions testers.
Testing found that all of the companies were using a legal loophole that allows them to back down on emissions treatment in certain circumstances, a measure that is meant to protect engines. German regulators argue that this loophole is not always justified or necessary.
The recall of these vehicles will tighten the loophole to reduce pollution levels.
An internal investigation has been launched at Mercedes-Benz in the U.S. looking into its diesel emissions, while Volkswagen just announced that it has set aside $16.8 billion to cover the costs of its emissions scandal.