"Six months is enough," said Judge Charles Breyer in February, when he imposed a March 24 deadline for regulators and Volkswagen to agree how to modify 580,000 diesel vehicles.

Except that it wasn't.

Yesterday, Judge Breyer extended the deadline four weeks, to April 21, at the request of all parties involved.

DON'T MISS: Judge Tells VW To Find Diesel Fix By March 24: 'Six Months Is Enough'

The regulators are the U.S. Environmental Protection Agency and the powerful California Air Resources Board.

According to a news story from Reuters, both agencies supported Volkswagen's request for more time at a Thursday hearing in San Francisco.

Progress is being made, they agreed, but issues remain to be settled and no agreement has yet been reached.

2012 Volkswagen Passat TDI Six-Month Road Test

2012 Volkswagen Passat TDI Six-Month Road Test

Reuters reports that one outstanding issue may be whether some non-compliant TDI diesel vehicles could remain on the road, as a news story suggested earlier in the month.

Of more than half a million vehicles from VW, Audi, and Porsche with 2.0-liter 4-cylinder and 3.0-liter V-6 TDI diesel engines, 325,000 are not fitted with a Selective Catalytic Reduction ("urea injection") system.

Many experts speculate that those vehicles simply can't be made compliant with emissions standards.

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Whether VW must buy them back or could compensate owners and regulators in some other way is apparently one of the points still under discussion.

The diesel scandal that emerged six months ago has claimed numerous VW Group executives, both in Germany and North America, cut the company's value, and damaged its reputation for engineering.

Numerous public-relations gaffes by executives and the group's communications arm in Germany have only contributed to the company's woes.

2012 Volkswagen Passat TDI Six-Month Road Test

2012 Volkswagen Passat TDI Six-Month Road Test

Meanwhile, Volkswagen stresses that while owners wait for regulators and the company to come to an agreement, the cars remain safe to drive.

No new or certified-used diesel vehicles are being sold by dealers of any of three brands, although they can legally sell non-certified used diesel cars.

To read all our stories on the VW diesel issue since it broke in September, see our Volkswagen diesel scandal news page.


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