[bri3d]

The A4, Q5, Q7, Touraeg, Phaeton, and a lot of other VW vehicles which used the same 3.0TDI have the exact same rated power, which suggests that the engine calibration probably was shared as well. So I think it's plausible that Porsche dropped the engine in, went through their usual drive testing and tuning, and never thought about the emissions since they were already handled on the VW side.

[TheHolyLancer]

Porsche have a bit more go juice than a lot of the other stuff.

If they did a ECU remap (likely) coupled with some hw changes to the engine (maybe, maybe not), they would likely have at least suspected something.

Like, I can tune my Lancer Evo, with stock parts, to around 360 chp / 290 whp from 291 chp / 220 whp. This will put more strain on the parts, to nuke the little gas mileage, up the emissions (no CARB), and void the warranty on the drivetrain. In order to do that the ECU needs to be flash (by say cobbs tuning) and if there was a cheating thing they will need to be aware of it or else it'd be likely gone in the flash.

If I was to put on new parts and make it go even more... Then for sure you need a new tune to make it actually work properly.

[bri3d]

The rated horsepower on the 3.0 TDI in the Cayenne is the exact same as in all of the other applications I listed - do you have any source that it had a different map installed? I'm kind of basing my whole theory on the concept that it didn't because the rated output is identical.

[TheHolyLancer]

The thing has a 150 kW to 191 kW rating, granted on closer look it seems the Porsche one is shared across a lot of trims so maybe they didn't see it.

https://en.wikipedia.org/wiki/List_of_Volkswagen_Group_diese...

guess audi is the one that could be in deeper trouble.

[mrpippy]

I wouldn't be surprised if Porsche customized the throttle mapping and/or transmission programming. ECU remapping would be a bigger job though