dirty but clean BMW and the emissions-tinkering loophole

Believe it or not, German law allows car makers to manipulate exhaust emissions under certain conditions. Carmakers have exploited this, but a legal case against BMW may soon make it harder.
Exhaustive tests.

Hell broke loose at BMW in December, when a German environmental group accused the luxury carmaker of manipulating emissions. BMW, so far untouched by VW’s diesel scandal, denied the charge that its 320d model unlawfully emitted more toxic gases under certain conditions.

The firm ran its own tests. The data resulted in a dispute between the carmaker, Germany’s transport ministry and two environmental agencies over the process that determines how much toxic gases a car can emit under different circumstances.

The scrap reveals a loophole in European law. When VW used software to artificially cut emissions during lab tests and raise them on the road, it was fraud with a capital F. But in BMW’s probe, it is about real driving, outside the lab, and when emissions-cleansing devices are switched on.

The problem in BMW’s case is a foggy formulation covering what exactly constitutes regular driving and when software kicks in to reduce exhaust-cleaning to protect the engine. This step increases emissions levels of fine particles and nitrogen oxide; such pollutants cause around 432,000 premature deaths in Europe per year.

Often car emissions controls aren’t created for regular driving, but solely to pass lab tests. Karl Huber, professor, Ingolstadt Technical University

Both BMW and the environmental group tested the car in question. Both found that its software reduced or shut down exhaust-cleaning, thereby increasing emissions under specific conditions, namely when the motor hit a certain level of revolutions per minute. BMW argued the law permits this. Under German law, emissions-cleaning must be active under normal conditions, though it can be reduced in particular situations.

The environmental group wrote to the Federal Motor Transport Authority and public prosecutors in Munich, stating that toxic emissions increased when the car accelerated or went up a hill.

Now, the prosecutors and Berlin’s transport ministry and accompanying transport authority, are weighing whether revving up hills or gathering speed count as "normal."

According to Karl Huber, a professor in motor construction engineering at Ingolstadt Technical University, many cars reduce emission-cleaning in every-day driving conditions, and so emit more fumes. The professor was not surprised by the results of the environmental group’s measurements. Often, Mr. Huber said, car emissions controls aren’t created for regular driving, but solely to pass lab tests – and that the law permits this. “If BMW capitalizes on that, they are in line with the law," he said.

BMW is not alone; ultimately, thanks to the lack of clarity, most carmakers take advantage of this legal gray zone. But time is ticking as the Transport Ministry and prosecutors weigh up what normal driving really means.


Martin Seiwert writes about the auto industry for WirtschaftsWoche. To contact the author: [email protected]