Another shoe dropped yesterday in the continuing Volkswagen diesel-emission cheating scandal, as VW Group of America announced the immediate departure of its president and CEO Michael Horn.

With the scandal now approaching its six-month anniversary, values of used Volkswagen TDI diesels continue to drop, and VW sales are falling while the time it takes to sell them is increasing.

Meanwhile, owners of the affected Volkswagen and Audi TDI models and Porsche diesels are no closer to knowing how their cars will be updated than they were when the EPA released the news that VW engineers had admitted to using "defeat device" software in their emission-control systems.

DON'T MISS: VW delayed on diesel cheating to try to cut deal with regulators, lawyers say

Horn will be replaced "on an interim basis" by Hinrich J. Woebcken, recently named head of the North American Region and chairman of VW Group of America.

Horn, 54, had joined VW in 1990, and was well-liked by U.S. dealers now struggling with both stocks of vehicles they can't sell and continuing public concern over the Volkswagen brand at large.

“During his time in the U.S., Michael Horn built up a strong relationship with our national dealer body," said Herbert Diess, CEO of the Volkswagen brand in Germany, in a statement thanking Horn for his service, "and [he] showed exemplary leadership during difficult times for the brand."

2012 Volkswagen Passat TDI Six-Month Road Test

2012 Volkswagen Passat TDI Six-Month Road Test

An analysis of 42 million data points by Autolist, meanwhile, showed that prices for Volkswagen vehicles not involved in the scandal have fallen 2.4 percent--and those for the TDI vehicles that can still legally be sold are down 6.4 percent.

Non-scandal Volkswagens are spending more time on market before they sell, the site says, 13 percent above average at 106 days.

ALSO SEE: VW to release diesel cheating report by end of April, annual meeting to come June 28 (UPDATED)

It's far worse for the TDI models, which now spend an average of 178 days on saleor 88 percent higher than the market average.

Some of the buyers Volkswagen may be losing could be turning to domestic brands, Autolist suggests.

2012 Volkswagen Passat TDI Six-Month Road Test

2012 Volkswagen Passat TDI Six-Month Road Test

Brand perception for Chevrolet and Ford has increased the most among all brands--at 1.3 percent and 0.7 percent respectively--since the diesel scandal broke.

And the lineups from both Ford and Chevy are selling fasterthough that could also be helped by their strength in crossover SUVs and a number of new models from Chevrolet.

CHECK OUT: Judge Tells VW To Find Diesel Fix By March 24: 'Six Months Is Enough'

Perhaps the most interesting data from the analysis shows that while the volume of internet searches for Volkswagen has fallen, searches for comparable Ford and Chevy models has risen 14 percent and 12 percent respectively.

Volkswagen's U.S. sales fell 8.7 percent last month compared to February 2015, in a surging U.S. market that set a new volume record last year. Its sales are down 8.8 percent for the two months of this year.

Global sales for VW fell 2 percent last year, though its 2015 sales in the U.S. were up by 1.2 percent.


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