Daimler Investigates 'Possible Irregularities' In Emissions Testing

German automaker Daimler AG is conducting an internal investigation into possible anomalies in its emissions certification process, the company confirmed Thursday. The development comes at the request of the U.S. Department of Justice, which contacted Daimler last week.

"Daimler is cooperating fully with the authorities," the company said in a written statement. "Daimler will consequently investigate possible indications of irregularities and of course take all necessary action."

Justice Department officials could not be reached for comment Thursday, but its query may address the BlueTec diesels manufactured by Daimler's Mercedes-Benz unit. In February, US owners of the vehicles filed a lawsuit against the company, alleging the BlueTec pollution-control technology turns off at cooler temperatures.

Plaintiffs allege the company's cars contain a defeat device similar to the ones programmed in nearly 600,000 Volkswagen diesels nationwide. In the BlueTec case, court filings claim nitrogen oxide reduction systems turn off when temperatures drop below 50 degrees. As a result, affected cars pollute the environment at an average of 19 times the federal threshold set by the Clean Air Act.

Daimler said the lawsuit's claims are "without merit" and that the Justice Department investigation is unrelated.

Thursday's Daimler developments, of course, come only hours after Volkswagen reached a tentative agreement with US authorities to buy back hundreds of thousands of vehicles that contained defeat devices designed to cheat on emissions tests. Details on the settlement are still unclear, but car owners with vehicles equipped with 2.0-liter engines may be entitled to further damages that a federal judge called "substantial compensation."