Volkswagen May Need to Fix Software 'Cheat Device' With Hardware
NEWS ANALYSIS: Just because a software routine can make VW's diesel cars seem clean doesn't mean you can fix it with new software.To borrow an idea from the late legendary cartoonist Walt Kelly and his beloved possum Pogo, Friday the 13th came on a Wednesday for Volkswagen this month. Jan. 13, 2016, was the day when Volkswagen CEO Matthias Müller was planning to reveal the car maker's plans to fix its diesel emissions problem to U.S. Environmental Protection Agency Administrator Gina McCarthy. Apparently, the plan didn't pass muster because Müller left after an hour without saying anything. Volkswagen's problems actually began nearly 10 years ago when engineers figured out that they could install a routine into the engine control computer that was able to discern when the car was undergoing an emissions test. When it detected such a test, the computer modified the control program so that the car would pass the test, but as researchers discovered, that routine only worked when the test was under way. This meant that during routine driving, Volkswagen diesels put out more emissions than were allowed. Exactly how bad those emissions were depended on how the car was being driven, and on the type of emissions control system installed. Some older diesels emitted nearly 40 times the level of nitrogen oxide than was allowed. The "cheat device" software (as the EPA calls it) figured out when the car was being tested by watching the relative speeds of the front and rear wheels. When the front wheels were turning but the rear wheels weren't (which is what happens during a dynamometer test used for emissions testing), then the control computer knew that a test was going on.
The obvious question then becomes, if the control computer can make the car clean enough sometimes, why can't it do it all the time? Depending on the type of emissions control system that's installed in the car, that might work, but for older Volkswagen cars, it won't. Apparently to make those cars clean enough, the engines won't perform adequately for real-world use. Some newer cars, however, may be able to be fixed with a software change.