The fuel industry's American Petroleum Institute tested the 15 percent ethanol gas approved in 2010 and found it gums up fuel systems, prompts "check engine" lights to come on, and messes with fuel gauge readings.
Now, according to a new study, cars and truck may face the same fate thanks to President Obama's demand for a higher ethanol in the new E15 gas.

The additional E15 testing, completed this month, has identified an elevated incidence of fuel pump failures, fuel system component swelling, and impairment of fuel measurement systems in some of the vehicles tested. E15 could cause erratic and misleading fuel gauge readings or cause faulty check engine light illuminations. It also could cause critical components to break and stop fuel flow to the engine. Failure of these components could result in breakdowns that leave consumers stranded on busy roads and highways. Fuel system component problems did not develop in the CRC tests when either E10 or E0 was used. It is difficult to precisely calculate how many vehicles E15 could harm.
In 2010 and 2011, EPA gave the green light to use E15 - the 15 percent ethanol gasoline blend - in model-year-2001-and-later cars and some other vehicles. EPA's action was irresponsible. EPA knew E15 vehicle testing was ongoing but decided not to wait for the results. Why did EPA move forward prematurely?