In case there was any question as to whether Volkswagen's multi-year deception over emissions performance on its widely popular 2.0-liter diesel engine was just a handful of evil engineers programming Earth-killing code into some Jettas, there's some additional information to consider this week: the company just disclosed to US regulatory bodies that it had a second emissions control system installed in its 2016 models, AP reports.

It's not clear whether the new system is a "cheat," though. We're not talking about the "defeat device" that the EPA has been talking about since last month — this is a different system, which VW is referring to as an "auxiliary emissions control device." The system apparently quickly heats up the NOx trap — the device that traps harmful nitrogen oxides from diesel exhaust — which makes it perform better. Volkswagen claims that such a system "is subject to approval by the agencies" and that it's in the process of submitting additional information about what it is and how it works.

Heating up the NOx trap sounds innocent enough, but it might simply come down to when it's turned on: if the system is designed only to engage when the vehicle is undergoing an emissions test, that's a cheat. If it's always on and it demonstrably reduces emissions, then that seems like it's on the up and up, as long as the EPA is cool with it. Either way, it's suspicious that Volkswagen apparently didn't disclose the existence of the system until last week, well after the cheating scandal broke. (VW is currently trying to get permission to sell its 2016 diesel models in the US, where its approval was pulled in the wake of the scandal.) The EPA says that it hasn't yet determined whether the new system is a cheat or a legitimate emissions reduction tool.

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