Auto/Economy
10:44 am
Fri January 21, 2011

Will more ethanol in gas lead to more engine damage?

The farm lobby has been pushing hard to increase the amount of ethanol allowed to be mixed into gasoline. And it seems like the Obama Administration is obliging.

The vast majority of today's ethanol comes from corn. The alcohol is mixed in gasoline to make it burn more cleanly.

Right now, the standard is 10% (a 10% ethanol, and 90% gasoline mix is most likely in your gas tank right now).

The EPA increased the allowed amount of ethanol to a 15% mix last fall for cars made after 2007.

Now, the Associated Press reports the EPA is poised to allow the 15% mix for more cars. From the AP:

Two people familiar with the decision said late Thursday the agency is expected to announce on Friday that 15 percent ethanol in gasoline is safe for cars manufactured between 2001 and 2006. Both officials requested anonymity because they were not authorized to speak publicly about the decision.

Automobile manufacturers have said an increase in the ethanol mix could damage vehicles. They've sued the EPA over the increased standard.

You can't get the 15% mix yet, and it could be awhile before we see the new fuel at gas stations.

The EPA is still working on rules that would stop people from mis-fueling their cars (accidentally adding the 15% mix to an older car, for example). And fuel makers have to complete an "E15 fuels registration application" - AND the EPA says some state laws have to be modified to allow for the use of E15.

Officials at the EPA say they've tested the new blend and deemed it safe for certain cars.

So why the worry, how can ethanol damage a car or an engine? Popular Mechanics has an excellent article on how ethanol can damage engines - basically in three ways:

  1. "Phase separation" - more water in your tank = engine no go
  2. "Corrosive alcohol" - it can degrade plastic, rubber or even metal parts in the fuel system
  3. "Freeing the gunk" - alcohol canĀ  "scour varnish and deposits out of the fuel system that have remained in place for years, which will eventually wind up in the filter or main jet, choking off the engine's fuel supply."

The PM article concludes:

An energy policy that mandates more domestic production sounds like a great idea. But sneaking more ethanol into the supply stream at the expense of people who rely on their cars, boats and outdoor power equipment might better be left to the marketplace and not to bureaucrats.

Is adding more ethanol to our fuel good for farmers and good for our country (boosting domestic fuel supply)? As long as you follow the label, the EPA says E15 won't do damage.