We don’t claim to be ethanol experts, but the more we learn about the fuel additive, the less we like it. Sadly, we now have even more reason to dislike E15. Tests are now showing that the E15 fuel mix can harm cars built after 2001 according to a recent API press release.

E15 – a gasoline blend with 15 percent ethanol – was green lit by the EPA in 2010 for mass-market implementation in order to meet the federal Renewable Fuel Standard.

This E15 blend has been shown to cause fuel pump failures, fuel system component swelling, and impairment of fuel measurement systems. E15 can also cause erratic and misleading fuel gauge readings or faulty check engine light illuminations. Additionally, E15 has been found to cause damage in engine valve and valve seats.

This is just one more nail in the coffin of ethanol as a mass-market fuel substitute. Ethanol, which mostly comes from corn in the US, has been promoted as a renewable fuel source. This couldn’t be further from the truth. Corn is produced through a hugely un-renewable agriculture industry. If that weren’t enough, ethanol contains less energy than gasoline so fuel efficiency is diminished with its use.

Ignoring its negative environmental impacts, ethanol, when specifically applied, can be a great fuel in the right application. Take the Koenigsegg CCX for example. When tuned to run on E85 (85 percent ethanol) the CCX power output is upped from 800 horsepower to 1018.

Unfortunately for those of us without a Swedish supercar, increased ethanol execution will only cause vehicle damage and breakdowns. So when you see a gas pump marked with an E15 sticker, avoid it.