More than two years after it was first announced, Mazda's SkyActiv-D diesel engine still hasn't made it to the U.S.--and it doesn't appear that will change in the near future.

The 2.2-liter four-cylinder engine was originally slated for the Mazda 6 mid-size sedan, but concerns over performance have continually delayed it.

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That's reportedly still the case, and the engine may not be a high priority for Mazda at the moment.

The diesel engine still doesn't have the performance Mazda wants, Jim O'Sullivan--the company's North American CEO--told industry trade journal Ward's Auto at the recent Chicago Auto Show.

2016 Mazda 6

2016 Mazda 6

The diesel's status quo apparently hasn't changed much recently.

As he said back in December, O'Sullivan claimed the Skyactiv-D engine meets all of the necessary emissions regulations, but doesn't provide enough sportiness to match the brand's "Zoom-Zoom" image.

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Development work has also been sidelined as Mazda prepares to launch several new products--including the 2016 MX-5 Miata sports car and CX-3 crossover--O'Sullivan said.

The U.S. version of the Skyactiv-D will likely use a urea injection system for exhaust aftertreatment, although Mazda had initially hoped to get by without fitting the system's tank and plumbing.

2016 Mazda 6

2016 Mazda 6

The company had previously claimed its engine could meet U.S. emissions standards without urea--something no passenger-car diesel fitted to any 2015 vehicle sold in North America can manage.

Crucially for the small automaker, omitting a urea system would lower the cost of fitting the diesel engine to any vehicle. It shares many components with the Skyactiv-G gasoline engines now used in the Mazda 6, Mazda 3 compact, and CX-5 crossover.

If nothing else, Mazda customers are getting a chance to show just how patient they can be.

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The company says customers "lauded" the decision to delay the diesel, saying they don't want to spend money on a half-baked product.

The diesel-powered Mazda 6 was originally supposed to go on sale in Spring 2013, but that was eventually pushed back for a year, before being delayed again.

Now, Mazda won't discuss a timeline for the diesel's launch. At this rate, it's conceivable that the Mazda 6 will be redesigned before the Skyactiv-D engine becomes available.


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