Hundreds of thousands of diesel-VW owners are waiting to find out how their cars will be updated to meet emissions standards, once modifications are approved by regulators.

And Volkswagen Group has clearly been tarnished by the emission-cheating scandal, which affects 11 million cars worldwide.

But the costs of the entire affair remain to be tallied; some analysts have said that the 6.5 billion euros ($7.1 billion) set aside several months ago will not be nearly enough.

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A Bloomberg article earlier this month cites an estimate by Bloomberg Intelligence that payments and buybacks for owners in the U.S. alone could range from $1.5 billion to $8.9 billion.

And those are just the damages or buyback payments that "customers should get for being duped into buying high-polluting vehicles," it notes.

About 157,000 of the 482,000 affected 2.0-liter TDI diesel cars sold in the U.S. with "defeat device" software are already fitted with Selective Catalytic Reduction aftertreatment systems (also known as urea injection).

Consumer Reports tests 2015 Volkswagen Jetta TDI diesel in 'cheat mode,' October 2015 [video frame]

Consumer Reports tests 2015 Volkswagen Jetta TDI diesel in 'cheat mode,' October 2015 [video frame]

They're likely to require no more than software updates or perhaps minor hardware tweaks to bring them into compliance. VW then might only have to pay owners for diminished value, plus some penalty.

But for 325,000 VW Golfs, Jettas, and Beetles and Audi A3 cars without the SCR systems fitted, the prognosis is much grimmer.

Most analysts agree that the cost and complexity of retrofitting a urea tank, a different catalyst, and all the associated plumbing could exceed the value of cars that are now as much as seven years old.

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Those cars, some suggest, may all have to be bought back and either destroyed or exported.

Using an average price of $15,000, that would cost $4.9 billion alone--before any civil or criminal penalties are levied.

On top of the hundreds of thousands of 2.0-liter four-cylinder TDI cars, 85,000 more VW, Audi, and Porsche vehicles were sold in the U.S. with a 3.0-liter V-6 TDI engine. That engine contains several undisclosed software routines, and one of those qualifies as a "defeat device" as well.

2015 Audi A3 TDI, New York City, Nov 2014

2015 Audi A3 TDI, New York City, Nov 2014

The admission by Volkswagen that it cheated makes the case close to unique, suggests Paul Hanly, a plaintiffs' lawyer quoted in the Bloomberg article.

It may point to an early settlement, he says, since culpability doesn't have to be established first. All that's left is to settle on the costs and penalties.

That just applies, however, to more than 450 lawsuits filed by Volkswagen customers in the wake of the mid-September disclosure.

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On December 8, those lawsuits were consolidated and will be heard in California, where a high proportion of the affected TDI diesel vehicles were sold. The state also has a large number of VW dealers.

Volkswagen had opposed the designation of California, asking that the suits be heard in Detroit instead. That did not happen.

On top of the customer lawsuits, which will lead to cash payments and perhaps buybacks, Volkswagen faces criminal investigations in several states.

2012 Volkswagen Passat TDI Six-Month Road Test

2012 Volkswagen Passat TDI Six-Month Road Test

But no settlements can move forward until regulators agree on modifications to the various sets of vehicles to bring them into compliance with tailpipe emission laws.

Volkswagen submitted its proposals for those updates to the U.S. Environmental Protection Agency and the California Air Resources Board in November.

On December 18, CARB extended its own deadline for responding to VW's proposal until mid-January.

That leaves owners in a holding pattern at least until then, and likely far longer.

Volkswagen stresses that all the TDI vehicles involved in the scandal are safe to drive, and urges owners to continue to do so.


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