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Ethanol Free Gas - Topping off my vehicle tank - Waste of money ???
September 24, 2023, 12:46 PM
4MUL8REthanol Free Gas - Topping off my vehicle tank - Waste of money ???
If you find benefits, continue using fuels as you describe. My profession is as an engineer in the world of vehicle fuels, and I'll offer a few bits here.
1. Ethanol as a fuel offers less energy than gasoline. No getting around this chemical fact. So, ethanol free fuel has more energy, and to move down the road, some distance, requires less fuel.
2. Many vehicles either calculate or measure the ethanol content of the fuel, and adjust injector pulse width and strategy real time. Your vehicle is aware, compensating, and maximizing its performance for each tank.
3. Ethanol is often criticized, but modern vehicles all can function well with up to 10% ethanol. Flexible Fuel Vehicles (FFV) can consume up to 85% ethanol. Bringing concerns about small engine carburetor or marine use of ethanol fuel to the typical vehicle is not truly relevant.
4. Ethanol is an effective solvent, and is known to provide a cleaning benefit for soluble deposits found in the combustion chamber and valves.
5. Octane requirements are to be followed. Preignition due to low octane, poor quality fuel, or other causes can damage pistons and rings.
6. Ethanol-free fuel naturally provides more energy per combustion cycle, and as a result could mean the driver is not demanding as much of the engine by opening the throttle. This could be a reason for not sensing "pinging" but at the OP's stated fuel tank proportions, this surprises me.
7. Of importance to the average driver is the cleanliness of the fuel injectors. Detergents in fuels are required by EPA, but the quantity of the detergents at "lowest additive concentration" is low. Top Tier fuel has significantly more detergency. Premium fuels from global fuel retailers are even higher in detergency.
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Trying to simplify my life...
September 24, 2023, 03:02 PM
Fly-Sigquote:
Originally posted by 4MUL8R:
2. Many vehicles either calculate or measure the ethanol content of the fuel, and adjust injector pulse width and strategy real time. Your vehicle is aware, compensating, and maximizing its performance for each tank.
Can you give a brief explanation how it does that which the non-scientist could understand? Some kind of electrical resistance or capacitance measurement?
September 24, 2023, 04:28 PM
4MUL8RIn older vehicles (such as a 2013 GMC Sierra) the ethanol content is estimated from the mass air flow sensor, the oxygen sensors, and the awareness that the tank has been filled (the level sensor). Driving away from the pump, for a minimum of a few miles, the computer continues to adjust injector pulse width (time the injector is open) to achieve proper air-fuel ratio. It is like saying "well, I had to shoot two dozen .22 rimfire rounds to obliterate the bullseye, but it only took seven .45." The computer program estimates what must be in the fuel tank. These sensor readings give an estimate of the ethanol content, which is stored in the computer until the next fueling event.
For vehicles with an actual ethanol sensor, the fuel passes through the sensor and a direct reading is made. This signal is interpreted by the computer and allows a direct calculation to adjust the injector pulse width. We've checked the accuracy of the sensor at our lab, and found it reads 10% ethanol when we blend a 10% ethanol fuel for testing.
The exact method for measuring ethanol is not universal. Various internet pages offer some concepts.
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Trying to simplify my life...
September 24, 2023, 04:51 PM
Fly-SigThanks for the info!
September 24, 2023, 10:31 PM
TRIOA friend of mine has a Toyota with a 10.8:1 compression ratio engine. She said she was getting knocking noises. I told her to start using midgrade gas with 89 or higher octane until she can get her knock sensors checked or replaced. Been two months with no noise. Now she is just using that gas instead of the expense of the fix issue.
--Tom
The right of self preservation, in turn, was understood as the right to defend oneself against attacks by lawless individuals, or, if absolutely necessary, to resist and throw off a tyrannical government.
September 24, 2023, 10:38 PM
parabellumI find that when I top off my tank, it contains more fuel than it did before I topped it off. The way I use this to my advantage is being able to drive farther before running out of fuel, although this is not to say that I drive my automobile until it's so completely not topped off that the engine won't run. Doing so makes it impossible to reach a gas station where I top off my tank.
You get the idea.
I don't know the compression ratio of my engine. Frankly, I don't think it has one of those.
September 25, 2023, 05:37 AM
pbslingerIs ethanol free fuel tested and certified by state agencies similar as E10 and other road fuels?
September 25, 2023, 07:09 AM
TRIOThe original post mentions the following:
2012 Tacoma V6 truck
NO motor “pinging”
My comment about my friend is because she was having similar issues with similar car. Thinking back to the days before ECM adjusting engines, the octane recommended was determined by compression ratio of the engine.
The Toyota mentioned is possibly the 2GR-FE engine which has a minimum of 10.8:1 ratio. 4MUL8R's post about sensors knowing ethanol concentration before ignition was enlightening. I only knew of knock sensors detecting issues during ignition. With my past experience with similar vehicles, I suspected the ping or knock could be from ECM getting bad signals.
So that is why I recommended the octane level & checking the knock sensors. It solved her issue, perhaps it may help others.
Ethanol free gas, which was part of the original post question, usually only has 89 octane. That's why I didn't even mention it.
September 25, 2023, 07:12 AM
DanHquote:
Originally posted by TRIO:
Ethanol free gas, which was part of the original post question, usually only has 89 octane. That's why I didn't even mention it.
Not in my area. Over here it's either 91 or nothing.
September 25, 2023, 09:30 AM
Fly-Sigquote:
Originally posted by TRIO:
Ethanol free gas, which was part of the original post question, usually only has 89 octane. That's why I didn't even mention it.
Here in Utah, pure-gas is available as mid grade or premium or even higher premium. Boaters and off-road recreational vehicle owners are a big market for pure-gas.
Our grades of ethanol fuel are 1 octane less than in most of the country, which is a now out of date concession to the higher elevation. Carbureted engines don't knock as readily here, ergo the lower octanes.
Modern engines (due to combustion chamber designs) and turbocharged engines still need the recommended octane. This can cause problems when people are used to selecting by grade (e.g. "Regular") rather than octane.
The pure-gas here frequently is 1 octane higher than the same grade E10, putting it at the same octane as the rest of the country. And there is one station selling 95 octane pure gas. The pure-gas is usually priced 15% higher than E10, so there is no mpg incentive to buy it.
September 25, 2023, 09:59 AM
rizzlequote:
Originally posted by smlsig:
I was debating on wether or not comment about using an additive occasionally to help clean out the engine but since someone else did…
I have been using a can of Chevron Techron in our vehicles about once a year and I get slightly better mileage when I do. I attended a Tech talk several years ago by an automotive engineer who recommended it and have been using it ever since.
You can find it in just about any autoparts store.
If you have pinging that goes away with a slight increase in octane I suspect the knock sensors are working, especially if there are no codes.
Carbon build up is the most likely cause, I have never used Seafoam, the Techron however is known to work very well.
September 25, 2023, 01:54 PM
jhe888quote:
Originally posted by trapper189:
Is the gas you get pinging with 87 octane?
Is the ethanol free you are adding and then not getting pinging with 90 octane?
Would the lack of pinging and increased mileage be a function of the increased octane rather than the added gas being ethanol free?
Next time, I’d skip the ethanol free, try the 89 octane, and see if the results were the same.
It really shouldn’t be pinging in the first place. How many miles on the engine?
Lastly, since the engine runs better and your mileage increased, you are not wasting $2. Over 400 miles that $2 saves 1.6 gallons of fuel.
Agreed - pinging is caused by low octane fuel in an engine that needs it, often because it is a higher compression engine. Try the mid grade ethanol fuel and see if it pings. The ethanol itself should not cause pinging.
But it shouldn't - that Taco does not have a high compression engine. It should run just fine on low-test.
The fish is mute, expressionless. The fish doesn't think because the fish knows everything. September 25, 2023, 02:00 PM
HRKNon Ethanol is for lawn equipment, small engines, older engines not setup for E10 use, where the parts can degrade from exposure to the alcohol in the fuel.
JMO not worth putting into a newer vehicle they can all run E10 without an issue.
September 25, 2023, 03:59 PM
TRIOLooks like I was wrong...2012 Tacoma has the 4.0l v6 1GR-FE engine with 10:1 compression.
I still think higher octane fuel is a good choice for OP issue.
--Tom
The right of self preservation, in turn, was understood as the right to defend oneself against attacks by lawless individuals, or, if absolutely necessary, to resist and throw off a tyrannical government.
September 26, 2023, 09:35 PM
jimmy123xquote:
Originally posted by TRIO:
Looks like I was wrong...2012 Tacoma has the 4.0l v6 1GR-FE engine with 10:1 compression.
I still think higher octane fuel is a good choice for OP issue.
10:1 compression is pretty high. A top tier regular unleaded might solve the pinging issue of the motor only requires 87 octane by the manufacturer. I'd say the lady needs to do a few full throttle runs.
September 26, 2023, 09:55 PM
maxwayneI often top off with non-alcohol when I fill my 5 gallon can for my lawn mowers. I get better mileage when I use all non-alcohol, but it is not cost efficient.
September 27, 2023, 12:51 PM
egregoreI can't tell any difference in how my car runs with ethanol free, but my wallet can tell the difference. About $6 a tankful.
Any car made in the last ~30 years is already OK with E10.