Commentary: Why VW’s ‘defeat device’ is different from what happened in trucking
The current situation surrounding the VW emissions scandal parallels trucking’s emissions difficulties that led to the “consent decree” in 1998.


Maybe the most meaty and interesting story ever for an automotive journalist is the current Volkswagen diesel mess. A giant company, with a pretty good reputation in consumers’ eyes, boldly cheats by using clever engine-management software. It produced compliant emissions performance under test conditions but opened the floodgates in ordinary driving and let loose 10 to 40 times more NOx than allowed by the rules.
That’s how VW diesel owners have been able to brag about their 50-plus-mpg cars. Thing is, you can’t limit NOx and particulates and get great fuel economy at the same time. Those of us in trucking know that only too well.
The worst part is that Volkswagen admits that this deception — of the authorities, car buyers, its own dealers — was deliberate. It’s an extraordinary tale of corporate malfeasance. The arrogance is astonishing.
It remains to be seen what the company will do about it.
The legitimacy and competence of the Environmental Protection Agency is also called into question here. A political body, never a scientific one, it knew about Volkswagen’s cheating in May 2014 but did nothing, choosing instead to accept the German outfit’s version of things and its unkept promise of a fix.
There are parallels of a sort with trucking’s emissions difficulties that led to the “consent decree” in 1998. The U.S. Department of Justice charged heavy-duty engine makers with using a “defeat device” as defined by the Clean Air Act, not unlike the one in the news today. But it was actually quite different in practice, so don’t go thinking they behaved like Volkswagen.
The engine folks never admitted guilt, signing the consent decree agreement and paying $83 million in fines in order to move on. It was really EPA’s crude testing procedures and imprecise rule-making that were at fault. For all intents and purposes, the EPA threw engine-makers under the bus — in an election year.
Its test procedures back then were way out of date, set up for carburetion and mechanical fuel injection, not the increasingly sophisticated electronic controls that were in use.
Engine makers felt their only legal obligation was to meet the test-cycle standards in order to secure an EPA compliance certificate. And a very well informed source tells me that one truck maker had a letter from the EPA saying exactly that.
So engine makers set the ECU to meet the NOx limit on the EPA’s test cycle but optimize the engine for fuel consumption and performance under other circumstances.
When the EPA started making accusations about “defeat devices,” truck and engine people cried foul. At least one lawsuit was filed against the EPA, by Mack, and the chances of winning actually looked pretty good. But the EPA countered with bullying, including threats to ban the sale of Mack engines. Soon the fight was over, truck- and engine-makers deciding that discretion was the much better part of valor.
Ya can’t fight city hall.
For their troubles and their imagined sins they were hit with those heavy fines, but the more onerous penalty was that the 2004 EPA emissions mandate was pulled ahead by 15 months to 2002. That cost the industry at the time something like $820 million. But we all know what not having enough time for development and testing of those engines cost both manufacturers and truck users in the long run.
Billions.
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