[JSH]

Originally Posted by Fat Charlie

Fake news, actually. There's really not much to it on Chrysler's end. It was in the software and it was very well optimized for the EPA tests and when driven like a normal person was dirtier

Yes, Fiat's engines where "well optimized" for the EPA test in that they turned off emission controls when the vehicle recorded conditions outside of an EPA test. These include:

Temperature - Above 95F and below 50F
Speed - Above 60 mph
Miles - After 12 miles have been driven

Now none of this is new. Automakers have been installing defeat devices since the emission testing started. Some examples:

1. In 1973 Chrysler, Ford, GM, Toyota, and VW got caught changing fuel mixture based on temperature outside of the test conditions
2. In 1996 GM got caught turning off emission controls when the heat or A/C is on (They aren't on in the test)
3. In 1997 Ford got caught turning off emission controls when speeds exceed the maximum on the EPA test
4. In 1998 Honda got caught changing spark advance to allow more pollution when speeds exceed the maximum on the EPA test
5. In 1998 pretty much every heavy duty truck manufacture got caught dialing back emission controls when the truck exceeded the maximum time for the EPA test. (This was the first time the fine / repair was in the billions of dollars)