The Volkswagen diesel settlement approved by a federal judge earlier this week does not address all of the company's cars fitted with illegal "defeat device" software.

It covers only VW and Audi TDI models with 2.0-liter 4-cylinder engines, sold in the U.S. from model years 2009 through 2015.

It's good news for the 475,000 owners of those vehicles, but it leaves the 85,000 owners of VW, Audi and Porsche TDI models with 3.0-liter V-6 engines in limbo.

DON'T MISS: Audi V-6 diesel talks 'progressing well' for October agreement, exec says

The next hearing related to those vehicles is scheduled to take place on November 3, but now a report out of Germany offers some interesting news.

Audi will buy back 25,000 Q7 TDI SUVs, according to Reuters, which cited a report that appeared in the German newspaper Der Spiegel from last Friday.

The Q7 TDI is one of multiple Audi models with the 3.0-liter V-6 diesel engine found to have "defeat device" software.

2013 Audi Q7 TDI S Line

2013 Audi Q7 TDI S Line

The others are the Q5 TDI SUV, A7 TDI hatchback, and A6 TDI and A8 TDI sedans.

Diesel versions of the Porsche Cayenne and Volkswagen Touareg SUVs use the same engine as well.

Buybacks are expected to be a part of the V-6 diesel settlement, just as they are a major focus of the approved settlement for 4-cylinder cars.

ALSO SEE: How VW's 3-liter diesel cheat worked; fate unclear for V-6 TDI vehicles

In February, VW Group submitted a plan to the EPA and the California Air Resources Board to modify its 3.0-liter V-6 diesel engines.

Audi and Porsche executives had said that simple software modifications, and possibly the fitting of new catalytic converters, would bring the affected vehicles into compliance with emission regulations.

That plan was rejected in July by regulators, using particularly stern language.

2013 Audi Q7 TDI S Line

2013 Audi Q7 TDI S Line

CARB said VW's descriptions of its proposed modifications were "incomplete, substantially deficient, and fall far short of meeting the legal requirements to return these vehicles to the claimed certified configuration," according to its letter.

Modifications still haven't been approved for any of the affected diesel vehicles with either engine.

Both CARB and the U.S. Environmental Protection Agency (EPA) must approve any emissions-related modifications made to affected vehicles.

MORE: Audi, Porsche, VW 3.0-liter V-6 diesel fix rejected by California regulators

Owners of the 2.0-liter vehicles will have roughly two years to decide whether to take a buyback, giving them time to learn if any modifications are in fact approved for any of the affected vehicles.

The next official milestone for the 3.0-liter TDI settlement will be a November 3 hearing in which all parties involved will provide an update on progress.

The hearing was scheduled by U.S. District Court Judge Charles Breyer, the same judge who has handled the 2.0-liter TDI settlement.


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