Running on real gas

Congrats on your purchase and excellent mileage. My 5 month average (Jan 13th to July 13th) is now 50.3 mpg according to the MFD using 10% Ethanol Shell gasoline

Where and did you find a station without 10% Ethanol? Did you just know one gas station without it or?

 

No Gulf gas stations in MD

 

hmmm since im in cali, i dont quite now the mixtures set on our gas...i use shell gas most of the time, and the rest i use unocal, mobil or chevron, which is convenient besides a shell station...no arco or cheap gas
and i use 91octane 100% of the time avg to date is around 42mpg mostly fwy and cruise speeds of 70+mph

 

When I read the title of this thread I thought you had converted the Prius to run on propane gas, after all petrol is a liquid not a gas.

I don't notice any difference using E10 or unleaded petrol.

 

It's chemistry, guys: E10 cannot reduce MPGs versus straight gasoline more than 3%. If you see a bigger difference it's coincidence, caused by different outside temps or different routes used on the different fillups, or unconscious changes in driving technique in support of the expected difference. Buy the E10, help clean the air (and clean the engine, BTW), and enjoy life.

 

My parents said in NY they were getting 30 MPG pretty constant with their car (an Avalon). From what I understand NY uses ethanol everywhere. Last week they went to PA and got gas. From what I understand in PA they do not use ethanol anywhere. Anyway their mileage went up to 35 MPG.
But now I'm hearing PA does use ethanol in some stations? So does ethanol use go by state or station?

 

Do not use high octane gas in the Prius. You can damage your car and you are at best wasting your money. Higher octane gas is only useful in large engines designed for it.

That's the 100% consensus in this forum

 

Hi Richard, I remember you posted the same on my thread. How much difference is there in Prius emissions using 100% vs 90% gas? I mean if this 10% Ethanol mix means a proportional drop in mpg isn't the result that for the same distance one will need more 90% gas?

And for the same distance won't the prius emissions be the same?

 

No it isn't! Speak for yourself.

You will never damage your engine using too high octane fuel.
You might damage your fuel system using fuel which has too much alcohol like E85 but high octane will not hurt your engine.

Alcohol in the fuel helps to keep the internals of the engine clean by burning off carbon deposits. It also removes water from the fuel system.

Simple maths says if E10 has 10% alcohol and alcohol has at least 70% of the energy an equal amount of petrol has then there can only be at most a 3% increase in consumption. (90% petrol + 7% for the 10% ethanol = 97%)

 

Please point out to me where I said that high octane fuel will damage your engine. I said it "will damage your car".

 

how will hi octane damage your car???

i mean these cars are made in japan, and they have even higher octane ratings than we do here in the US???

i always saw it as feeding a human body fast food versus healthy organic food LOL

 

From the Tech Training manual:

 

Sorry my mistake but it isn't 100% consensus (which was my point) as I still disagree. I run 94 and 95 RON fuel with no problem and it is OK according to Toyota to use E10 which is 94 or 95 RON. E10 is 4 cents per litre cheaper so it doesn't harm your wallet either although as a percentage that should be 6 cents a litre now. Someone is making a little extra profit somewhere.

Bill, what you show says don't use premium it says nothing about E10 which has a higher octane rating than 87 unleaded but lower than premium.

 

wow thanx for the 411

 

Richard,

I haven't sat and worked out the stoichiometry, but I'll take your word for it it.

However, based on my own limited experience with E10 (I know for sure that I've had one tank), I'm not sure that I agree that there is no effect. I'm equally unsure that any effect can be written off to an unconscious change in driving technique. The only way I know to really solve this is run double-blind tests with fuel from known sources.

I don't have by myself the ability to run those trials. But would be interested in this. I thought I saw an effect from E10, but there's no way of really knowing without doing the experiment. I have my own hypothesis that I'm working through, but without data it's really just conjecture.

 

Do you mean CO2 emissions? Being lazy and not working through the chemistry right now, and if I understand the question correctly: the 3% drop in MPGs will mean a roughly 3% increase in CO2 emissions per mile traveled.

It's not worth stressing about this because at the end of the day there's very little to be done about it. E10 is used in all US cities of any size to reduce carbon monoxide and hydrocarbon pollution. It would be counterproductive to drive, say, 50 miles out of your way (25 miles each direction) into the boondocks just to fill up on straight gas. That would increase your CO2 emissions 10% or more, and reduce your *useful* MPGs by the same amount.

 

Forget about the driving to the middle of nowhere to find that gas. I mean that's not what the question is about. But if we agree that we will travel a certain distance won't we need more E10 fuel? Aren't we simply increasing the frequency in which we refuel for a certain distance?

 

Yes. Fewer miles-per-gallon means you have to buy fuel more frequently. With E10 you can only go 97% as far as with straight gasoline. So for example in five years one might have to fill up 103 times with E10 instead of 100 times with straight gas.