Almost two years ago, the Volkswagen diesel emission scandal burst into public view, and nothing has been quite the same since then.

The news that VW Group engineers had deliberately cheated on eight years of emission tests for the "clean diesels" sold by Volkswagen, Audi, and Porsche sent shockwaves around the world.

Settling the criminal charges in the U.S. for almost 600,000 diesel vehicles has cost VW more than $25 billion, but multiple European investigations remain underway.

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Only this year did European emission standards for diesels tighten to match the U.S. standards in effect since January 1, 2008.

That means that a lot of the diesel cars sold in EU countries over the last 10 years were too dirty to sell in North America.

The ones sold before 2005, in fact, were simply filthy, emitting large volumes of nitrogen oxides and also particulate matter of multiple sizes, a clear cardiopulmonary health risk to humans.

Mercedes-Benz A Class diesel: UK drive

Mercedes-Benz A Class diesel: UK drive

Real-world emissions on European tests prove to be far higher than the legal limits, although all the vehicles sold were certified as compliant under some rather narrow interpretations of test procedures.

Now multiple European cities have proposed banning older vehicles and various diesels from entering city centers altogether.

In light of all this, four European carmakers who have sold large numbers of diesel vehicles are offering buyback programs under which older cars get four-figure incentives to turn in their old diesel car for scrapping if they buy a new car from the same brand.

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As detailed by the British outlet Autocar, German media reports have covered a variety of trade-in and scrapping schemes for older diesel vehicles.

The incentives range from €1000 ($1,180) to €7000 ($8,250) on top of the vehicle's normal trade-in value, though details vary among manufacturers. 

They're being offered by Mercedes-Benz, Fiat Chrysler (including Alfa Romeo and Jeep), numerous Volkswagen brands, and Opel, previously a unit of General Motors and is now owned by PSA Peugeot Citroen.

Volkswagen TDI 'clean diesel' television ad screencap

Volkswagen TDI 'clean diesel' television ad screencap

The buyback offers are the result of a "Diesel National Forum" summit meeting held among German automakers and government authorities.

Broadly, diesels certified under Euro 1 to Euro 4 standards (through the 2008 model year) will be bought back and scrapped, while many more recent Euro 5 and Euro 6 cars will be reprogrammed to reduce NOx emissions.

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BMW and Ford in Europe are reportedly close to launching their own buybacks, and many if not all carmakers seem likely to extend the programs from Germany to the U.K. and other countries as well.

In a statement affirming Volkswagen's acceptance of the forum's recommendations, VW Group CEO Matthias Müller said, "Our comprehensive package of measures will significantly reduce NOx emissions and significantly improve air quality."


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