The EPA has changed its policy on corn-ethanol blends, and states may soon change their formula 15 percent ethanol. The problem with that? There are fears might void your warranty or damage your car. Also, from the article:

"The only group that really seems to like the new rule is the ethanol lobby.

"'We've force fed a fuel into every American's car that benefits a few thousand corn farmers and ethanol refiners at the expense of virtually every other American,' EWG's vice president of governmental affairs, Scott Faber, told Mother Jones.