On Mon, 28 Sep 2015 19:28:43 +1000, Sam Thatch wrote:

The cheatware detects when a motor undergoes emissions testing,
and then

how is that possible?

As others have said by some physical anomally that wouldn't occur
in
the real world or by the "brain" knowing what the testing profile
is.
ie stationary at idle for 15 seconds, 1st gear to 10 mph in 4
second
2nd gear to 20 mph over 3 seconds, 3rd to 30 mph in 3 seconds,
hold
for 30 secs, up to 40 in 5, up to 4th hold for etc ....

That second possibility wouldn't work. By the time its noticed that
pattern, it's too late to run the engine so that the emissions would
be good enough to satisfy the test.

Disagree you could be pretty sure after the first three driving steps
above, 10 seconds. ISTR that the tests take about half an hour, 10
seconds in "dirty" mode is going to be masked by the following 1790
in "clean" mode.

--
Cheers
Dave.