Your cheatin' heart

Seized documents support allegations of collusion in Dieselgate

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The AdBlue blues. Source: DPA

Investigations into diesel emissions cheating among German carmakers also unearthed a conspiracy to further defraud diesel drivers. Investigators found documents that show carmakers colluding to limit the amount of a liquid that helps clean diesel emissions. The liquid, known as AdBlue, was central to the emissions-cheating devices built into the cars that unleashed the Dieselgate scandal in 2015.

AdBlue neutralizes harmful nitrogen dioxide in diesel emissions and is a mixture of urea and water. It was contained in a separate tank but the tank was too small to hold the amount of Adblue needed to neutralize emissions for the full distance between servicing. Engineers thought it would turn off customers to diesel if they had to refill the tanks themselves every couple of months.

“That would be a disaster for the entire clean diesel strategy in North America,” one of them wrote in a 2008 email. Instead, the engineers installed software that allowed Adblue to reduce emissions during testing, but severely limited or stopped the flow of the reagent on the road, vastly increasing the noxious emissions well above legal – or advertised – limits.

Adblue tanks too small

The documents are part of a criminal investigation of 39 suspects associated with VW for fraud and deceptive advertising. In addition to possible criminal charges, the companies face heavy fines if collusion on emissions cheating or other practices is proven. The news comes as a trial opens on a suit by VW investors claiming €9 billion in losses due to deception about Dieselgate.

Among the 16,000 pages of documents investigators have are other emails that indicate possible collusion among the carmakers to limit the size of the Adblue tanks even though they were too small. “This assessment is held also by VW, BMW and Daimler,” a widely distributed Audi email said.

Handelsblatt reported last year about a presentation by Audi that indicated the carmakers all thought the tanks needed to be small. It spoke of “a commitment of the German automotive manufacturers at board level.”

Other documents show that all three had submitted uncannily similar requirements to suppliers for the size of the Adblue tanks. The specifications indicated that one liter of Ablue per thousand kilometers would be sufficient to neutralize the nitrogen dioxide, when in fact it would require at least three liters, one engineer told investigators. The amount in the specified tank would never last for the 16,000 kilometers (10,000 miles) between servicing.

“Defeat-device task force”

The documents indicate the automakers were well aware of the problem. An email from a VW department head to a Daimler engineer in 2012 sounded an alarm because of a meeting scheduled with authorities who had spoken of “indications of an Audi, BMW, Daimler, Porsche and VW defeat-device task force.”

The carmakers declined to comment, repeating only that they are offering their full cooperation in the investigation. BMW, in particular, drew a distinction between the collusion allegations and the defeat-device investigation, noting it has not been accused of emissions cheating. The company said it knows nothing about a defeat-device task force.

In the meantime, Handelsblatt has learned that a number of VW managers who were summarily dismissed last month after prosecutors let the carmaker review its investigation files are suing VW for wrongful termination, claiming the company was responsible for the diesel policy. They include former head of development Jakob Neusser, and engine chiefs Rudolf Krebs and Falko Rudoph. Their lawyers declined to comment.

Volker Votsmeier is an editor with Handelsblatt’s investigative reporting team. Jan Keuchel is a Handelsblatt correspondent covering investigations and the German legal system. Martin Murphy covers corruption in industry. To contact the authors: and

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