The German government has announced the start of a voluntary recall of 630,000 Audi, Opel, Mercedes-Benz and Porsche to fix emissions irregularities uncovered in the wake of the Volkswagen emissions scandal.
Germany's Federal Motor Transport Authority - Kraftfahrt-Bundesamt (KBA) stated that the recall would start with refits for 10,500 Porsche Macan SUVs.
The voluntary recall which was first announced in April after an investigation into various German carmakers over high levels of health-threatening nitric oxide (NO) diesel emissions.
The recall is aimed to ensure that a legal loophole allowing manufacturers to throttle back emissions treatment systems below a certain outside temperature. With the treatment systems deactivated, the cars do not meet European emissions regulations.
However, German investigators accept Porsche, Mercedes, Opel, and Audi's claim that the temperature based deactivation was necessary to prevent damage to the engine. This ensures that the recall is a voluntary and not a compulsory one like the one faced by Volkswagen for its use of emissions test cheating software.
However, the voluntary recall will ensure that the temperature window for the emission treatment deactivation is narrowed down so that it corresponds to "the actually necessary extent" needed to keep the engine safe.
Volkswagen on the other hand, plans to recall 8.5 million cars worldwide out of which 2.4 million are in Germany.