Two days after the Environmental Protection Agency took the unusual action of issuing a motor vehicle recall for nearly 500,000 Volkswagen and Audi sedans that used software to circumvent emissions tests, the car maker says it will stop selling all vehicles equipped with the same kind of diesel motors as those involved in recall.

VW announced on Sunday that it would stop selling all model year 2015 and 2016 — both used and new — Volkswagen and Audi models equipped with 4-cylinder turbo diesel engines marketed as “clean diesel,” reports the New York Times.

Martin Winterkorn, VW CEO, publicly apologized on Sunday for the issue.

“I am personally deeply sorry that we have broken the trust of our customers and the public,” he said in a statement, adding that the company would “fully cooperate” with both federal and independent investigations.

While a VW spokesperson didn’t know how many vehicles would be affected by the stop sale, previous sales reports estimate the company sold 7,400 new diesel cars in August.

On Friday, the EPA ordered Volkswagen to recall nearly 500,000 vehicles over concerns the automobiles expose people to harmful pollutants.

The EPA initiated the recall through a notice of violation [PDF] of the Clean Air Act, after an investigation found the automaker intentionally installed software in 482,000 diesel 4-cylinder model year 2009 to 2015 Volkswagen and Audi vehicles as a way to evade emissions standards for certain pollutants with a range of serious health effects.

The software – known as a “defeat device” – was first detected during independent analysis by researchers at West Virginia University who were working with the International Council on Clean Transportation, a non-governmental organization. The findings raised questions about emissions levels, and the EPA, along with the California Air Resources Board, began further investigations into the issue.

“Using a defeat device in cars to evade clean air standards is illegal and a threat to public health,” Cynthia Giles, Assistant Administrator for the Office of Enforcement and Compliance Assurance, said in a statement.

Models covered by the recall include the model year 2009 to 2015 Volkswagen Jetta, Beetle, Golf, and Audi A3, as well as model year 2014 to 2015 Volkswagen Passat sedans.

According to the notice, the “sophisticated software algorithm” in the vehicles is programmed to detect when the car is undergoing official emissions testing, and to only turn on full emissions control systems during that testing.

However, the effectiveness of these vehicles’ pollution emissions control devices is greatly reduced during all normal driving situations.

Following the recall order, our colleagues at Consumer Reports decided to suspend the “Recommended” ratings it had previously given the Passat diesel and Jetta diesel.

“These recommendations will be suspended until Consumer Reports can re-test these vehicles with a recall repair performed,” reads a statement from the publication. “Once the emissions systems are functioning properly, we will assess whether the repair has adversely affected performance or fuel economy.”

The EPA’s investigation — and subsequent recall — could eventually lead to a fine or penalty for Volkswagen, the NYT reports.

Under the Clean Air Act, the Justice Department could impose fines of as much as $37,500 for each recalled vehicle, for a possible total penalty of as much as $18 billion.

Winterkorn said the company would “do everything in order to reverse the damage this has caused.”

Volkswagen to Stop Sales of Diesel Cars Involved in Recall [The New York Times]

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