According to the Environmental Protection Agency (EPA), Volkswagen Group's V6 TDI engine has now been found to use emissions cheating software similar to that used on their 2.0-liter four-cylinder diesel engines last month. Unfortunately, the 3.0-liter TDI engine, the subject of a new report released today by the EPA, can be found in the engine compartments of 2015 Porsche Cayenne Diesel models, extending this issue outside of just Volkswagen and Audi.
Breaking EPA, California say @VW used "defeat device" in some six- cylinder (3.0 liter) diesel vehicles including some Porsche vehicles
— David Shepardson (@davidshepardson) November 2, 2015
According to the report, the discovery that the 3.0 V6 diesel is also involved in this scandal covers an additional ten-thousand vehicles (VW, Audi and Porsche combined) sold in the US between the 2014 model year and today. It is likely that all 3.0-liter TDI-powered vehicles will be included on the stop-sale list after these findings.
The report details that the software determines when the car is being tested (FTP 75 Federal emission test procedure) and directs the vehicle to change some parameters in order to produce a more favorable, and more importantly passable, NOx emission. The control parameters include injection timing changes, increased exhaust gas recirculation rate, and common rail fuel pressure, changing them in such a way as to yield low engine-out NOx emissions, as well as much higher exhaust temperatures. The hotter exhaust temperatures activate the "selective catalytic reduction system" and improve the catalyst's ability to reduce tailpipe NOx. The so-called 'temperature conditioning' is then deactivated exactly 1-second after the federal testing procedure has been ceased, and the engine will run in "normal" mode when the software determines that the car is not undergoing FTP 75 Federal emissions test procedure.
The report goes on to explain that the software knows the exact time duration of the federal testing procedure, and deactivates the "temperature conditioning" mode exactly one second after testing ceases. Further, the vehicle will automatically run in "normal" high-emitting mode "when the vehicle starts under conditions that the software determines are not the beginning of the FTP 75 Federal emissions test procedure."
When Volkswagen's 2.0 TDI scandal came to light, I made it a point to ask a Porsche representative whether there might have been any concern regarding the 3.0 liter unit, and was told that the company or their customers had no reason to believe such a thing was possible. In keeping with that off-the-cuff not-exactly-a-statement statement, Porsche's official stand on the matter is simply relayed in the official company statement sent out this afternoon.
Late this morning, Porsche Cars North America, Inc. received a notice of violation from the United States Environmental Protection Agency (EPA) regarding the 2015 Porsche Cayenne Diesel.
We are surprised to learn this information. Until this notice, all of our information was that the Porsche Cayenne Diesel is fully compliant.
Porsche Cars North America will cooperate fully with all relevant authorities.
The Justice Department and federal prosecutors are heading a criminal investigation against the Volkswagen Group that could lead to a very hefty fine, and in addition to that, the automaker currently faces more than 350 lawsuits here in the states. As news continues to develop regarding Porsche's involvement in the scandal, we'll keep you up to date.
[Source: Twitter, Road & Track]