He co-sponsored the bill in the Senate:
S. 768: Fuel Economy Reform Act A bill to increase fuel economy standards for automobiles and for other purposes. Co-sponsor: Sen. Joseph Biden [D-DE]
Requires an average fuel economy standard of 27.5 miles per gallon for all automobiles manufactured by all manufacturers for model year 2013, with an increase of four percent in the average fuel economy from the level for the prior model year for model year 2014 and beyond.