With full details of the Volkswagen diesel cheating settlement postponed again, VW TDI owners have an extra week to contemplate their diesel cars without knowing what they'll be offered in a buyback.

Earlier analyses of used-car pricing data showed that their value as used cars has fallen since the scandal broke last September.

Those vehicles also lingered on the market for an extraordinarily long time before they sold, if they did.

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Now a new study has confirmed the decline in value for VW and Audi diesel vehicles, and put some numbers on it.

CarGurus, a used-car listing service, analyzes millions of used-car listings daily to create what it calls an Instant Market Value analysis.

It analyzed a sample of the VW models affected by the emission-cheating scandal, and their nationwide asking prices.

Model of asking and projected non-scandal prices for used Volkswagen diesel vehicles [CarGurus]

Model of asking and projected non-scandal prices for used Volkswagen diesel vehicles [CarGurus]

The service ran a projected regression to calculate what their market values might have been absent the scandal.

That modeling showed that the median loss of value for a Volkswagen TDI diesel vehicle was $1,483, or almost 8 percent of the projected non-scandal value.

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That's higher than a previous value-loss calculation by Autolist, which analyzed 42 million data points in March.

The Autolist study showed that Volkswagen TDI models now spend an average of 178 days on sale—which is 88 percent higher than the market average.

2015 Volkswagen Passat TDI

2015 Volkswagen Passat TDI

And it calculated that prices for used TDI vehicles had declined 6.4 percent in that study, compared to 2.4 percent for Volkswagen vehicles not involved in the scandal.

From reader questions and comments, it's our sense that many owners of affected Volkswagen and Audi 2.0-liter diesel vehicles have simply shrugged and given up trying to sell their cars.

They seem to be waiting to learn the terms of the proposed settlement, namely at what value Volkswagen will offer to buy back their cars.

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The broad consensus is that VW will have to use the highest possible pre-scandal price—one for a car in excellent condition, regardless of what shape the cars it buys are actually in—and likely add some premium on top of that.

Note that any such purchase offer is separate from the fund for dispensing a rumored $5,000 to each owner who will waive rights to any future lawsuit against VW for selling a non-compliant vehicle.

Full details of the proposed settlement between Volkswagen and the EPA are to be released on Tuesday, June 28. A final hearing on the settlement will be held on July 26.


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