Volkswagen can begin updating roughly 38,000 SUVs illegally equipped with emissions-cheating devices, federal and state regulators announced Monday.

The EPA and California Air Resources Board sent a letter to VW, Audi, and Porsche officials Friday approving fixes for 2013-2016 Volkswagen Touaregs, 2013-2016 Porsche Cayennes, and 2015 Audi Q7s equipped with the 3.0-liter V-6 TDI diesel engine.

Fixes for the second-generation diesel engine will include software updates for all models, while 2013-2014 Cayennes and Touaregs, and 2015 Q7s will require some hardware modifications. A spokeswoman for VW didn't immediately say what those changes will be.

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Around 40,000 Audi A6, A7, A8, Q5 and older versions of the VW Touareg and Q7 with the older version of the 3.0-liter V-6 diesel engine are still in limbo. Last year, the EPA and CARB rejected fixes for those cars and VW could be liable for billions in additional penalties if those cars and SUVs can't be fixed. Reuters reported Monday that the automaker may save more than $1 billion with the updates announced Monday, but that sum is a relative drop in the bucket compared to the $25 billion amassed so far in fees and buybacks.

A spokeswoman for Volkswagen said that the company is working "with our regulators to develop approved solutions for the remaining 3.0L TDI V-6 vehicles as quickly as possible."


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