On Sun, 20 Sep 2015 16:29:30 -0400, Mitch Kaufmann wrote:

On Sat, 19 Sep 2015 00:19:10 +0000, Ewald Böhm wrote:

My question is HOW did the car *know* it was being *tested* for emissions?

http://www.usatoday.com/story/money/...agen/72436098/
The software code allows all of the car's emissions systems to work when the cars are taken in for clean-air testing. But as soon as the emissions tests are complete, the system reverts to spewing pollutants. The cars emitted nitrogen oxide at a level of up to 40 times the standard level, the EPA alleges.

That answers what.
But it doesn't answer HOW.