Global Automakers

15% Ethanol Fuel Raises Consumer Concerns; New Study Demonstrates Vehicle Failures in Popular Models

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May 16, 2012

Washington, DC -- Consumers could be paying more to repair their cars due to the adverse effects of fuel containing 15 percent ethanol (E15), according to new results from a two-year study on engine durability.  The study was conducted by FEV, a longtime consultant to the U.S. Environmental Protection Agency, on behalf of the Coordinating Research Council (CRC).

The CRC study released today showed adverse results from E15 use in certain popular, high-volume models of cars.  Problems included damaged valves and valve seats, which can lead to loss of compression and power, diminished vehicle performance, misfires, engine damage, as well as poor fuel economy and increased emissions.

“Clearly many vehicles on the road today are at risk of harm from E15.  The unknowns concern us greatly, since only a fraction of vehicles have been tested to determine their tolerance to E15,” said Mitch Bainwol, president & CEO, Auto Alliance.  “Automakers did not build these vehicles to handle the more corrosive E15 fuel.  That’s why we urged EPA to wait for the results of further testing.”
The potential costs to consumers are significant.  The most likely repair would be cylinder head replacement, which costs from $2000-4000 for single cylinder head engines and twice as much for V-type engines. 

“Our goal is to ensure that new alternative fuels are not placed into retail until it has been proven they are safe and do not cause harm to vehicles, consumers, or the environment,” said Mike Stanton, president and CEO, Global Automakers. “The EPA should have waited until all the studies on the potential impacts of E15 on the current fleet were completed.”

“Automakers believe that renewable fuels are an important component of our national energy security, but it is not in the longer term interest of the government, vehicle manufacturers, fuel distributors or the ethanol industry itself, to find out after the fact that equipment or performance problems are occurring from rushing a new fuel into the national marketplace,” said Bainwol.

Growth Energy, an ethanol industry trade group, petitioned the EPA in March 2009 to raise the limit on ethanol in gasoline from 10 to 15 percent.  In June 2008, EPA outlined testing needed for the agency to approve a waiver, and EPA requirements were consistent with test plans developed by the auto and oil industries.  The CRC, composed of engineers from the auto and oil industries, was working with EPA and U.S. Department of Energy (DOE) on a multi-year suite of tests on the effects of higher blends of ethanol.  This testing included more than $14.5 million of research sponsored by the auto and oil industries, and $40 million of testing sponsored by the federal government.

Before those tests were completed -- in October 2010 and January 2011-- EPA granted “partial” waivers to allow the introduction of E15 into the marketplace for use in model year 2001 and later vehicles.  EPA’s decision was based largely on a DOE study of the effects of E15 on durability of catalytic converters, the primary pollution control system in a vehicle.  EPA did not undertake or wait to consider the results of this engine durability test, or for other E15 related research still underway.

The CRC Engine Durability study took duplicates of eight different vehicle model engines spanning 2001-2009 model years.  All 16 vehicles were tested over a 500-hour durability cycle corresponding to about 100,000 miles of vehicle usage.  A range of engine operating parameters was monitored during the test, including cylinder compression, valve wear, valve leakage, emissions and emissions control system diagnostics.  Two of the engines tested on E15 had mechanical damage.  Another engine showed increased tailpipe emissions beyond the allowable limit.

This study adds to the body of knowledge on the effects of higher blends of ethanol.  Ten research papers have been published on the effects of increasing the ethanol blend ratio to E15 from the current E10.  In a study by the Oak Ridge National Laboratory on the impact on fuel dispensers, all gaskets, seals and O-rings swelled and showed effects that can result in leaks.  The National Renewable Energy Laboratory (NREL) tested samples of service station equipment, and found that, on average, about half of the equipment failed the compatibility tests.  Another NREL study found severe damage to marine engines run on E15. 

Automakers advise consumers to continue to follow the guidance on fuel selection in their vehicle owner’s manuals.  While automakers do market certain vehicles called Flex Fuel Vehicles (FFV) that can use up to 85 percent ethanol, these vehicles have been designed to tolerate the more corrosive ethanol, including changes to fuel pumps, fuel tanks, fuel injectors, engines, control systems, various calibration capacities, emissions systems and materials used. 

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The Association of Global Automakers represents international motor vehicle manufacturers, original equipment suppliers, and other automotive-related trade associations. Our members’ market share of both U.S. sales and production is nearly 40 percent. We work with industry leaders, legislators, and regulators to create the kind of public policy that improves vehicle safety, encourages technological innovation, and protects our planet. Our goal is to foster a competitive environment in which more vehicles are designed and built to enhance Americans’ quality of life. For more information, visit

The Alliance of Automobile Manufacturers is a trade association of 12 car and light truck manufacturers including BMW Group, Chrysler Group LLC, Ford Motor Company, General Motors, Jaguar Land Rover, Mazda, Mercedes-Benz USA, Mitsubishi Motors, Porsche, Toyota, Volkswagen and Volvo.  For more information, visit

For release:
May 16, 2012

Annemarie Pender, Global Automakers
(202) 650-5548
Gloria Bergquist, Auto Alliance
(202) 326-5596


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