Well, when I say properly tuned, it could be a decade old one. Not even new.
The attempt to shave fractions of a ppm, at the expense of tons of CO2 is folly. A minor change in NOx or particulates for tons of wasted fuel.
It all “jumped the shark” when a 50 MPG Vw diesel, “cheating” or not could be called a “gross polluter”, while an 8 mpg Ford suv could get a “partial zero emissions” certification. Absolutely obnoxious and ridiculous.
They just can vilify diesels easier because the NIMBY and coastal elite detached from reality idiots are mainly sheeple…. And those who “tune” diesels make it worse for everyone too. I love diesels. I don’t want to see black smoke everywhere. I’m good with smart tuning, better controls, even emissions controls… to a point… the point where we’re forced to not have access to diesels to appease California.