Not all of the automaker's guilt has been atoned for.
Back in 2019, Mercedes was fined close to a billion dollars for its part in the Dieselgate scandal. The following year, Mercedes announced that it would be spending over $2 billion on settling US civil and environmental cases. You'd think by now that the matter would be truly behind the German automaker, but unfortunately, it seems that we have not yet been told the truth, the whole truth, and nothing but the truth. According to a public report from Deutsche Umwelthilfe (DUH) dated November 5, 2021, Mercedes is still using eight emissions-cheating devices in a Mercedes-Benz E-Class with the Euro 6-classified diesel engine. These previously secret devices are said to effectively reduce nitrogen oxide emissions by a substantial amount.
For the record, the devices are not on a currently-produced E-Class. The report - commissioned by US law firm Milberg and carried out by automotive software expert Felix Domke - claims that a 2016 E 350d with the OM642 engine has six defeat devices connected to the car's SCR catalytic converter and another two for the car's exhaust gas recirculation system. The DUH deems these devices illegal and says that they are used to misstate emissions results during laboratory testing. In the real world, the engine produces as much as 500% more in nitrogen oxide emissions than the legal limit allows. Domke goes on to say that one of these devices "significantly reduces the amount of AdBlue injected, which is urgently needed to neutralize the nitrogen oxides in the SCR catalytic converter."
Interestingly, the German newspaper Automobilwoche reports that the Federal Motor Transport Authority (KBA) is aware of the devices and deems them legal. The KBA is the agency that discovered Mercedes-Benz's earlier cheat devices that resulted in the massive fines and settlements. It's probably for the best, especially from Merc's point of view, that the industry is shifting towards electrification, but this sort of thing is still likely to affect the way some perceive the brand and its level of integrity. Just don't expect to see a drop in sales - Mercedes is still more sought after than most mainstream brands.