is there any truth that e15 with the additional ethanol in it would produce more carbon deposits??? Are there any negatives other than slightly fewer tenths of mpgs to worry about??? in Iowa this stuff is pushed pretty well here with it being about 12-15 cents per gal cheaper at the local kwik star stations..offset of price not worth it??
e15 over e10 fuel worth it??
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Been running it for a couple of years in the 2016 F150 and 2021 Explorer. I buy it when it makes sense (at $4.00 a gallon, it made sense when it was about 10 cents a gallon or more cheaper.) I've typically been finding it 25-30 cents cheaper a gallon.
No issues I've noted.
No issues I've noted.
What do your owners manuals say about more than 10% ethanol? I'd be surprised if your '06 "Pontiyota" manual endorses E15.
I've chosen not to run e15 in anything the owners manual didn't explicitly state it was OK in. That was my choice anyways...
If it’s cheap enough to offset the mpg loss I run it… however in my area the local stations like to price their E15 at the same price as everyone else’s 87 E10.
Yes, check your manual to make sure you can run E15 safely. For older vehicles and small engines that is a real issue. My 2011 Ranger literature says explicitly not to run more than E10.
Ethanol is a powerful solvent, you won’t get more carbon running a higher ethanol content. I use it in every vehicle I have when I’m near a Casey’s. Their E15 88 is usually 15-18 cents cheaper than E10 87. I don’t even notice any difference in mileage.
Some engines do poorly with any ethanol. Some do quite well. My E85 capable 5.4L does not really care about octane, but add any ethanol to the mix and MPG drops into the zone of sadness. 16-18 MPG is possible on ethanol free fuel, 12.3 on E10 and about 8 on E85.
My Jaguar X-Type needs octane and MPG drops wildly with low octane. It really does not care how much ethanol is in the mix.
My Jaguar X-Type needs octane and MPG drops wildly with low octane. It really does not care how much ethanol is in the mix.
That is in reference to E85, not E15. If you look at the owners manual, its even under the header "Switching Between E85 and Gasoline".
The power potential from the raw fuel itself is roughly the same for E0, E10, and E15.
The ethanol improves intake air cooling by +31% for E10 and +44% for E15.
The throttle response and drivability is a wash.
For an engine, cruising easy at 60 mph @ 2000 rpm, with partial throttle and 40 CFM air consumption, at stoich AFR, will have a resulting fuel economy of... (theoretically)
E0 = 3.52 gallons per 100 miles = 28.41 mpg
E10 = 3.67 gallons per 100 miles = 27.25 mpg (-4.1%)
E15 = 3.73 gallons per 100 miles = 26.81 mpg (-5.6%)
Throw in E85 for the sake of it...
E85 = 5.06 gallons per 100 miles = 19.76 mpg (-30.4%)
The ethanol improves intake air cooling by +31% for E10 and +44% for E15.
The throttle response and drivability is a wash.
For an engine, cruising easy at 60 mph @ 2000 rpm, with partial throttle and 40 CFM air consumption, at stoich AFR, will have a resulting fuel economy of... (theoretically)
E0 = 3.52 gallons per 100 miles = 28.41 mpg
E10 = 3.67 gallons per 100 miles = 27.25 mpg (-4.1%)
E15 = 3.73 gallons per 100 miles = 26.81 mpg (-5.6%)
Throw in E85 for the sake of it...
E85 = 5.06 gallons per 100 miles = 19.76 mpg (-30.4%)
Honda approves up to e15, Subaru doesn't, and no way in the Pontiac...based on what i see here I'll continue to use it in the Honda only if price offsets the little loss in mpg's..I was just concerned since this is a tgdi engine...
We don't drive a ton of miles anymore and usually fill up for no more than 10 gallons. Saving a buck and a half ain't worth it to find out.
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In my town there is no stations that I have found that have e15, but when we go to Omaha to visit my son (85miles) I have filled up at the Caseys down the street from him with the e15, and didn't see any noticeable difference in mileage. Of course, since the tank is a long ways from empty when filling up, I really don't have fully e15 in the tank, as it is probably about 1/2 e10.
Oh also the vehicle is a 2017 Frontier v6 4.0 that is a flex fuel.
Oh also the vehicle is a 2017 Frontier v6 4.0 that is a flex fuel.
I question these results that show an MPG loss of more than 10% running E10 compared to E0. You would expect a mileage loss of 10% on E10 compared to E0 *IF* the ethanol contributed nothing to the combustion process...which is not the case.
Basically these results are saying that this vehicle goes further on 9 gallons of E0 than it does on 10 gallons of E10 (which is 1 gallon of ethanol and 9 gallons of E0).
That makes no logical sense.
Slightly OT but when I hand-mix E30 in my tank to run the “hot” tune I’ve got, between the tune and the fuel it usually shaves ~15% off the mileage. Part of it is fuel, but part is also because they reprogram the trans to hold gears longer and to eliminate the skip-shifts in the factory programming.
We run E15 in our 2005 Jeep GC and 2014 Chrysler T&C. In Iowa they usually incentive the use of E15. For running around town I don’t see any meaningful change in MPG that would negate the price. On the highway I try to stick with E10. I did notice about 2-3 MPGs difference between the 2 variations.
Just my $0.02
Just my $0.02
I have seen large drops after adding ethanol fuel to a vehicle that never ran it.
In one case the car had a bad head gasket leak and the ethanol helped to consume the water (that’s my story and I’m sticking with it) with e0 car had a slight miss, with ethanol ran like a racecar.
In the other the steel gas tank was full of sludge and water.
I expect if he really was seeing a big drop in mpg and kept running ethanol either his fuel filter would plug or the vehicle would start running better than ever.
In either event he should have noticed big drivability issues because “something “ was wrong.
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2-3mpg difference between 10 and 15 that's crazy...should be mathematically not possible...
We've got someone else in another thread claiming they get more than 10% better fuel economy on E0 than they do on E10.
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