The Mercedes-Benz E250 CGI BlueEFFICIENCY was a diesel-powered variant of the A207 Cabriolet that debuted for the 2010 model year. The E250 CGI BlueEFFICIENCY cabriolet was originally powered by Mercedes' M271 DE18 engine, which was a 201hp turbo 1.8L inline four. This engine was replaced for the 2014 model year by the M274 DE20, which was a new, more efficient inline four that had an output of 208hp. Both engines were offered with a manual or automatic transmission that sent power to the rear wheels.