The Environmental Protection Agency’s (EPA) recent approval of the E15 gasoline blend– a fuel mix of 85% gasoline and 15% ethanol – is drawing fire from AAA. The motorist advocacy group warns that less than 5% of cars on the road today are approved by automakers to use E15.

Based on a survey AAA conducted with OEMs, only about 12 million out of the more than 240 million light-duty vehicles on the roads today are approved by manufacturers to use E15 gasoline.

Yet, said AAA, EPA in June officially approved the sale of E15 after receiving a waiver request from producers interested in expanding the use of corn-based ethanol, despite objections by auto manufacturers.

AAA added that its automotive engineering experts  have reviewed the available research and believe that sustained use of E15 in both newer and older vehicles could result in significant problems such as accelerated engine wear and failure, fuel-system damage and false “check engine” lights for any vehicle not approved by its manufacturer to use E15.

“There is a strong possibility that many motorists may improperly fill up using this gasoline and damage their vehicle,” said AAA president & CEO Robert Darbelnet. “Bringing E15 to the market without adequate safeguards does not responsibly meet the needs of consumers.”

As a result, he warned, unsuspecting consumers using E15 could end up with engine problems that might not be covered by their vehicles’ warranties.

Five manufacturers– BMW, Chrysler, Nissan, Toyota and Volkswagen – are on record saying their warranties will not cover fuel-related claims caused by the use of E15, while eight additional automakers – GM, Ford, Honda, Hyundai, Kia, Mazda, Mercedes-Benz and Volvo – have stated that the use of E15 does not comply with the fuel requirements specified in their owner’s manuals and may void warranty coverage.

AAA noted that the only vehicles currently approved by automakers to use E15 are flex-fuel models, 2001 model-year and newer Porsches, 2012 model-year and newer GM vehicles, and 2013 model-year Ford vehicles. These approvals extend only to cars, light-duty trucks and medium-duty passenger vehicles (SUVs), AAA stressed, as the use of E15 is expressly prohibited in heavy-duty vehicles, boats, motorcycles, power equipment, lawn mowers and off-road vehicles.

“The sale and use of E15 should be suspended until additional gas-pump labeling and consumer-education efforts are implemented to mitigate problems for motorists and their vehicles,” Darbelnet added. “Consumers should carefully read pump labels and know their auto manufacturer’s recommendations to help prevent any problems from E15.”