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Ethanol in gasoline -- boon or bust?

I read and hear what sound like good rational arguments on both sides of the ethanol in gas issue. My 99 Jag now needs a new fuel pump and the mechanic says its due to the ethanol in the gas in Arizona. Is he likely right and if so is there anything I can do to prevent damage to engine parts in the future?

The ethanol debate kicks up often. We don’t want to get it started again.

Most cars can tolerate 10% ethanol. More than that is asking for trouble.

Brand new cars can handle a higher percentage, but more ethanol means less fuel mileage.

Even Al Gore now says it’s worthless, but it’s entrenched, so we’re stuck with it.

Since Ethanol is required in many areas, the argument that a new fuel pump was needed because of Ethanol does not make sense.  There were problems with it when it first came out, but for the most part they were minor. 

The only problem I have had was with my wife's car and some stations that were using a higher % and then only during the change of season time of ethanol caused some minor drivability issues, but no damage. 

Having said that, I believe there are some states that have dictated higher percentages of ethanol and that may be what the mechanic was referring to.  I will be interested in what others with different experiences than I have had.

My 99 Jag now needs a new fuel pump and the mechanic says its due to the ethanol in the gas in Arizona.

Your 11-year-old high maintenance luxury car needs a new fuel pump, and your mechanic blames the fuel? I don’t think so. I think you need a new fuel pump because you have a high maintenance luxury car.

There is one new news item: Gore admits his mistake in backing ethanol:

Fuel pumps don’t go bad because of ethanol.
They go bad because the owner drives around most of the time with a mostly empty gas tank.

The fuel pump needs the gas level to be high to provide cooling.
Fuel pumps get quite warm while running.


To be fair, he admits his mistake in backing corn ethanol. Corn ethanol is a loser. Waste-vegetation ethanol is more viable.

While I believe that ethanol is more politics than good science, ethanol did not cause permature failure of your gas pump. 11 years is not premature.

If you’ve allowed the gas to run out or you constantly “top off” the gas tank at gas stations to where the charcoal canister has become saturated and the tank can’t bretah in, that may have caused the pump to fail earlier than it otherwise would have, but short of one of those situations it’s fair to say it died a normal death.

10% ethanol shouldn’t damage any other parts of the car or fuel system. I’ll bet that your owner’s manual states that you can safely use 10% ethanol. If it says otherwise, post back. But, the car being 11 years old already and living in a hot climate, that doesn’t mean other parts won’t fail just from normal wear.

True. So is sugar ethanol. I should have specified.