Mazda has promised a diesel powertrain for its mid-size CX-5 crossover since the second-generation vehicle debuted in 2016. New evidence shows a CX-5 diesel is still on the way, but California has likely stalled things.

In a report from Green Car Reports, the publication discovered the CX-5 diesel has been certified for sale in California effective April 13. The certification indicates a diesel-powered CX-5 is still on the table, but the California certification process is a lengthy one.

Yet, don’t expect Mazda to begin shipping CX-5 diesels out to U.S. dealerships right away. A Mazda spokesperson confirmed with the publication that the CX-5 diesel has not yet undergone EPA certification and does not have federal fuel economy estimates.SEE

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When the crossover does finally arrive, it will be the only Mazda sporting a diesel engine. However, that could change. Future Mazda 3 and 6 variants could also gain the diesel engine.

Mazda has taken a separate path from many other automakers in the pursuit of fuel economy. As the industry moves to electrification and hybrids, Mazda has announced the development of its SkyActiv-X engine. The mill is a modified take on the HCCI (Homogeneous Charge Compression Ignition) engine. It takes the best of diesel and gasoline-powered engines and promises massive fuel economy gains and emission reductions without a hybrid system.