When I last bought a VW (2008) I was concerned due to a clunking noise after first starting it up and driving a few miles; I called the VW service dept and they explained that there was a compressor which captured exhaust fumes and released them at a lower rate for the first few miles of each journey -- to help them meet EPA emissions standards. I was assured there was nothing to worry about. While this is a differen…
Still I get your point: manufacturers are clearly going to optimize based on the measured metrics. How do we know those metrics are meaningful in the overall system.