At the other end of the spectrum, Acura has an entry luxury sedan, the ILX, which it hoped would draw young affluent buyers, one of the market's fastest-growing segments. But while ILX sales topped 10,700 in the first half of the year, it has received mixed reviews, at best, suggesting to some that Acura still hasn't figured out what it needs to be.
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The challenge that the ILX may have missed is "getting back to basics and making sure that [Acura] products are very different from those of the parent, Honda," said auto analyst Joe Phillippi of AutoTrends Consulting.
In the first half, Acura had a 6.2 percent year-over-year sales gain. Volume rose to 76,981 units, which was still well behind the numbers of key competitors.
The maker might have done better were it not for the 24.0 percent tumble by the MDX, the luxury SUV that saw sales slip to 18,214 compared with 24,117 in the year-earlier period. Acura officials note that they're wrapping up a model changeover, and they forecast that an all-new version of the MDX will bounce back in the months ahead. That could help Acura outpace the overall U.S. auto market recovery.
To ensure that consumers can't miss the new model, Honda recently launched what it is calling the biggest single marketing campaign in its 27-year history, which coincides with its switch to Mullen Advertising in Boston.
A deeper look at Acura's sales charts show that it sold just 44 of the quirky ZDX models in June, wrapping up one of the company's biggest bombs.
The costly mistake may have served as a much-needed lesson, American Honda's top U.S. executive, John Mendel, suggested. The ZDX was one of several flops marketed by both Acura and the mainstream Honda brand that were originally designed for Japan, Europe or other foreign markets and added to the U.S. lineup only incidentally—with catastrophic results.
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That won't happen again, say both Mendel and Accavitti.
"We're focused on improving our efforts in North America," said Accavitti. Though, he added, "we still see a very global potential."
Acura reportedly plans to launch production in China by 2016, joining the Honda brand in targeting what is now the world's largest auto market. It's an obvious step, as China is expected to also become the biggest luxury-car market by 2017.
The NSX, in particular, could give Acura global traction, but it will not be rolled out for some time. And Acura officials warn that they don't expect a quick return to the first-tier luxury brands.
"These things take time," Accavitti saod. It probably will take "a couple of years to see whether we move the needle."
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—By CNBC Contributor Paul A. Eisenstein. Follow him on Twitter @DetroitBureau.