Porsche is under investigation by German authorities due to potential manipulation of emissions testing results.

Volkswagen AG remains under the prying eyes of Germany’s motor vehicle authority KBA now courtesy of a probe of Porsche AG concerning potential manipulation of emissions data testing results of its gas-powered engines.

Porsche’s parent, VW, has been through a series of queries in Germany, the U.S. and other countries for a similar issue surrounding its diesel engines.

A KBA spokesman said Monday the investigation involves gas engines that Porsche made for the European market before 2017. Porsche confirmed that it informed the authorities after internal investigations uncovered suspected irregularities, according to Reuters.

(German prosecutors end probes into former VW execs for $1.8M.)

Several of Porsches vehicles produced between 2008 and 2017 are part of the investigation.

Porsche, famous for its high-prices sports cars, didn’t escape the diesel-engine scrutiny in the past. German prosecutors fined Porsche $632 million last year due to issues with their diesel emissions testing, but the sports car maker hasn’t been charged with anything on the gasoline side of the testing yet, according to Reuters.

The issues relate to vehicles developed several years ago, according to multiple reports, and that post-2017 models are not part of the investigation. Porsche officials said they are working with authorities on the investigation.

Bild am Sonntag weekly reported the investigation was focused on engines developed between 2008 and 2013, including those of the Panamera and 911 models, with suspected illegal changes to hardware and software that could affect exhaust systems and engine components, Reuters noted.

(VW denies Chairman Poetsch knew about scandal early.)

The news comes on the heels of a recent settlement by former Volkswagen AG Chairman Hans Dieter Poetsch. Poetsch and former VW Chief Executive Matthias Mueller are no longer being subjected to a probe after Porsche Automobil Holding SE agreed to pay a 1.5 million-euro, or $1.8 million, fine. The two were being investigated for failing to warn investors about the growing fallout of VW’s diesel emissions scandal.

Post 2017 Porsche vehicles aren’t part of the probe.

The move follows a similar move by prosecutors in May when they dropped charges against Poetsch and the company’s current chief Herbert Diess after the company agreed to a fine of 9 million euros, about $10 million.

In addition to their roles at Volkswagen, both Poetsch and Mueller were members of the board of Porsche Automobil Holding SE, the family-owned company which has 53.3% voting stake in Volkswagen AG.

(German automakers enduring more diesel-related scrutiny.)

Poetsch has long maintained that he was unaware of the cheating device used by VW engineers to skirt emissions testing until just before the brewing scandal was revealed by U.S. authorities in September 2015. This is in spite of media reports that he knew as early as June 2015.