Although it isn’t clear what effect E15 will have on cars, AAA president Robert Darbelnet believes that not knowing is reason enough to justify halting sales. On Tuesday February 26th, Darbelnet told Congress that the government hasn’t properly warned drivers about potential damage to their vehicles.

“The sale of E15 at this point in time is irresponsible,” he said. He stated in a testimony before the House Science Environment Subcommittee that sales should be stopped until additional testing allows for a consensus between ethanol producers and automakers about which vehicles can safely use E15. A study conducted last year in May suggested that E15 could damage older engines and that is a concern shared by motorcyclists and people who use recreational vehicles like ATVs.

“Residual fuel left in a fueling house could be detrimental to the performance of motorcycle or ATV engines due to the small size of their fuel tanks,’ American Motorcycle Association lobbyist and former senator Wayne Allard said to lawmakers. “The use of E15 will lower fuel efficiency and possibly cause premature failure. In off-road engines, the effect can be dangerous for consumers.”