Yup, spot on, @BaumerS4.

They would have been scrambling in the ‘06-’07 timeframe, to get the engine certified for sale in time for the launch of the ’09 model year. In retrospect the dropping of the diesel for the ‘08 model year is telling - they couldn’t get to the emissions standard, AND maintain competitive fuel consumption and…

Today’s diesels use injectors with controls that permit the time the injector opens (the start of the squirt) and closes (the amount of fuel squirted) in response to complex algorithms that incorporate data from sensors about the load on the engine, ambient air temperature, fuel quality, etc.

Using SCR actually reduces the amount of particulate matter captured in the filter medium, in comparison with a pure exhaust gas recirculation approach, as was used between 2002 and 2009. But, you’re right, all of this has added considerable upfront capital cost, reduced the capacity to carry freight, and added to the…

Soot is different from particulate matter, and is residue of contaminants in the fuel used. But, yes, particulate matter, a byproduct of the combustion process, increases as combustion temperature lowers, while NOx increases the hotter it gets in the cylinder. As NOx standards were tightened (EPA10 for big trucks…

Nonsense. This is a pure tone-at-the-top issue. Wanton, blatant violation of a sovereign nation’s statutes is not something minions will undertake unless they feel there is sanction at the top of the company. In VW’s “co-determination” model, the prime imperative is to employ IG Metall members, in Germany. The…

The heavy duty engine manufacturers didn’t “cheat” the test. The engines passed the test, and the engines that were sold were the same as the ones that passed. If the government grants you a mathematics degree without seeing if you can do long division, are you a cheater for claiming to have graduated?

NO. Not true. At steady state, partial load, as would be experienced driving on an interstate for extended period, the air/fuel map would “lean” out the mixture, meaning reduce the amount of fuel and increase the amount of air in the combustion chamber. This reduced the total amount of fuel consumed, which in turn…

No, this is not an exact parallel to the VW case. The engine OEMs met precisely the standard that was established by the EPA, and their products passed its tests. And would continue to have passed the tests, were the vehicles in which the engines were installed followed the same driving pattern embedded in the test…