Volkswagen said Wednesday that it would be able to bring its diesel cars into line with European clean air standards by updating engine software and installing a tubular part about the same diameter as the cardboard inside a roll of paper towels.
The technical patch that Volkswagen presented at company headquarters here is valid only for Europe, where it will be installed beginning next year. Modifying Volkswagen diesel cars sold in the United States will be more complicated because of stricter rules on emissions of nitrogen oxide, a pollutant harmful to the environment and human health.
But Volkswagen will have gone a long way toward overcoming the crisis it faces if it can fix the cars in Europe. Of the 11 million vehicles that the company has admitted programming to cheat on emission tests, the vast majority are in Europe, and about 8.5 million of those require repairs. About 500,000 of the cars are in the United States.
The automaker also said Wednesday that eight employees had been suspended in connection with an internal investigation to determine who decided to install illegal software in the vehicles, fewer than some news outlets had reported.
The company said it hoped the changes to European cars will not affect performance or fuel economy but could not yet guarantee that that would be the case.
Ferdinand Dudenhoffer, a professor at the University of Duisburg-Essen, estimated the cost of the recalls in Europe at 500 million euros ($532 million), only a fraction of the 6.7 billion euros that the company has set aside to cover the cost of the scandal.
“Volkswagen is finding its financial footing more quickly than expected,” Dudenhoffer said in an email. He noted, though, that Volkswagen still faced major risks, including fines by the U.S. Environmental Protection Agency and a slew of lawsuits by angry owners and shareholders.
Representatives of Volkswagen and its Audi division have been in talks with the EPA about how to make cars in the United States compliant.
Hans-Gerd Bode, a Volkswagen spokesman, declined to identify the employees suspended but confirmed that they include three top managers with responsibility for engine development. Software in the cars ensured that they were on their best behavior when being tested but allowed them to flout emission rules at other times.
The three managers have been previously identified as Wolfgang Hatz, who was in charge of research and development at Volkswagen’s Porsche division as well as head of engines and transmissions development for the Volkswagen Group; Ulrich Hackenberg, head of development for all Volkswagen Group brands; and Heinz-Jakob Neusser, head of development for the Volkswagen brand.
The mystery of what motivated the responsible people to risk the future of the company deepened, however, after Volkswagen presented a surprisingly simple way of fixing the cars, which it said it had been approved by German regulators.
Cars with 2-liter diesel motors can be repaired by simply updating the engine control software, the company said.
Cars with 1.6-liter motors will require installation of a tube that, based on a video shown to reporters, is slightly shorter than the cardboard inside a roll of paper towels and about the same diameter. The part, a so-called flow straightener or flow transformer, has mesh inside that is designed to stabilize air flowing into the motor. That allows the fuel injection system to function more precisely and to reduce emissions.
Volkswagen is still working on a fix for 1.2-liter motors but said it will probably consist of a software update.
Volkswagen said it will begin installing the fixes in January and complete the recall by the end of 2016.
The measures required in the United States are not likely to be so simple. The United States places stricter limits on nitrogen oxide, which is linked to lung ailments. In addition, most of the diesel vehicles sold in the United States — 320,000 from a total of 480,000 — are equipped with older emission technology that could be more difficult to make compliant.