We’ve already seen how TFLCar tricked the 2011 VW Jetta TDI during a dyno test, activating its “cheat mode” that curbs toxic gas emissions and reduces fuel consumption in order to pass emissions testing.
The people from Consumer Reports did a more detailed test with a 2015 VW Jetta TDI and a 2011 Jetta Sportwagen TDI in which they managed to trick the cars into “believing” they were on cheat mode while driving on the street.
Therefore, the consumer organization was able to assess how fuel economy and acceleration times are affected.
VW owners will not like the results, as both cars saw a drop in fuel efficiency and performance. The older model was 0.6 seconds slower from 0 to 60 mph (96 km/h), while fuel economy dropped from 50 mpg (4.7 l/100 km) to 46 mpg (5.1 l/100 km) on the highway.
The newer model loses only 0.1 seconds in the acceleration test, but drops from 53 mpg (4.4 l/100 km) to 50 mpg (4.7 l/100 km) in the economy test. While the differences may not seem that big, VW owners will certainly disagree if VW’s fix will be to simply put cars into cheat mode all the time.