Pure Gas ( No Ethanol ) experiment

There are ways to do better, such as count seconds between markers vs 0.1 odo ticks on the odometer to get finer resolution. Of course, this takes an OCD person of an engineering or measurement personality, plus very light traffic. Though the Prius central display allows this from passenger seats too.

Definitely true. I'm not much interested in any measurement test under 20 miles.

A fairly good section is I-90 in Eastern Washington. From the Columbia River at MP137 to the Idaho State Line at MP299, the only 'bust' discontinuity is at MP220 at Ritzville, where two adjacent mileposts are just a half mile apart. Though there are some other mileposts offset a bit from their correct positions due to topography (culverts, bridges, etc.)

 

Legally, the pumps have to be accurate. There is no legal requirement for the sensitivity of the auto shut off, nor the level of the pavement. Since filling the the tank until fuel is visible in the fill tube can damage the emission system, and most people don't want to bust out the jack and take 20 minutes to fill the tank, using the same station and pump controls for those variables when making tank to tank comparisons.

 

How so?

 

It isn't the engine emission system at risk. There are ones in place to control the emissions from fuel evaporation. Many, probably safe to say all, cars have a carbon canister on the fuel tank vent line for that purpose. Overfilling the tank can flood it, saturating the carbon to the point it no longer does its job. There could also be other components that can be damaged by the fuel.

 

Does anyone here use their GPS to mark the distance?

 

It would seem odd to put components in a fuel system that would damaged by the fuel.

 

I have, as an additional reference. Both the automotive GPS, and a hiking GPS with battery-saver mode turned off, matched up very well with my other reference.

 

As I stated, his reference is to a piece of "ethanol in gasoline industry" propaganda & ain't no reference, when it is untrue. A reference ain't a reference if it doesn't match the truth of other references. What YOU believe is that 1.8% is the same as 3%. Your piece of propaganda is untrue, showing you to be part of the "ethanol in gasoline industry" propaganda. Beyond 1.8% & 3%, is that 87 octane E0 gives 8%, 8%, 7%-8%, 7%, & 5% better MPG than 87 octane E10.

 

How many more times do you have to repeat all these before you believe that they'll come true?

 

A material rated to withstand fuel fumes may not hold up to repeated submerges in the fuel.
Remember, there are a lot of plastics in today's cars.

 

From a design perspective, putting materials where they are subject to failure in normal use due to chemical incompatibility is a recipe for warranty claims. I don't think that's a money-maker for Toyota or any other manufacturer. Particularly since the fuel system is part of the emissions system which has a longer warranty (very long in CARB states). Since there is nothing to prevent topping off the fuel tank, and since this is commonly done, and since doing so cannot be proven or disproven after the fact, I would think this would lead to warranty claims in case of a failure.

All my gasoline cans, and the tanks on my mower, chain saw and weed wacker are plastic. They haven't failed me, and the chain saw is almost 40 years old.

 

Define "topping off"?

The Camry manual says to stop filling after the fuel nozzle automatically clicks off, and to not top off. Other car manuals, that I recall, have said to fill to the first or second click. Going one or two clicks past that shouldn't be a problem. The chance of damage goes up when the tank is filled to the point where fuel is visible in the filler port. Some that strictly do that regularly. With test cars and economy runs, Wayne Gerdes will jump on the bumper and pull out the jack in order to fill up any air pockets in the tank(he's gotten gallons more than the stated fuel capacity on at least one truck).

I'm not saying there are components suspectable to damage from the fuel, but if there is, they won't contact the fuel until the tank has fueled way beyond what the manufacturer states to do. As for proving the cause, the carbon canister will be saturated, maybe flooded, with gasoline.

The tanks to many of your cars were also plastic. Emission regulations mean they cost much more than the tanks on your power equipment. If the manufacturer can save some on a part, like a vent line, that isn't in physical contact with liquid gas by using material rated for just fuel vapors, they might do so.

 

Makes sense. Thanks.

 

Actually there are all kinds of things in your car that could be damaged by the very thing they deal with. The carbon canister is to prevent gas vapors from escaping into the air and instead puts them into the intake system. "Topping" off can and will damage the canister and it is not a cheap replacement. Newer cars are less prone to this problem but it still exists. Topping off is actually illegal (though maybe not in all states?) and warnings are posted on gas pumps and in your owner's manual.

 

I wonder how that is enforced? I've never seen any cops near a gas pump checking for this. Even the attendant at Costco isn't checking for this.

Do you know of any states where this is illegal, and if so, where it is contained in their legal code?

 

Oregon. But this ban is primarily aimed at the service attendants, which are almost everywhere as self-serve is still mostly (though not fully, since 1/1/2018) illegal. The enforcers in this case are not the cops, but instead the captive customers who can file complaints.

I won't dig out the actual law, just point you to another state government source:

State of Oregon: AQ Programs - Top Off Ban

 

Seems like they included a big maybe in that law: "Topping off is when an attendant continues to fill a gasoline tank after the nozzle has clicked off. If an attendant can confirm that a vehicle tank is not full after the click off, the attendant may continue to dispense fuel using best judgment and caution to prevent a spill."

 

That is so that folks who occasionally suffer premature early pump shutoff -- it happens sporadically even on my Prius -- can still get a full refill.

I know approximately how much fuel should be dispensed before popping the cover, and the pump has stopped 3-7 gallons early more times than I can count. When that happens, I just pull the lever again.. And with no overflowing gusher, as a couple Oregon attendants caused on my prior cars before the top-off ban. That would now be prima facie evidence of a violation, which I would fuss over and demand a discount for the lost fuel.

 

It was illegal when I lived in CA as well but no idea of current laws

 

How many times do you avoid true evidence that the "ethanol in gasoline industry " is lying. Without planning, the use of 87 octane E0 in all 3 of our present Hyundai 87 octane, non-hybrid, un-supercharged, un-turbocharged cars were the only times individual tanks of gas had powered the cars to over 500 miles. & those facts occurred, despite more care needed to fill the E0 gasoline tanks sooner, because E0 stations are less commonly encountered. None of our Hyundai gas tanks, when filled with 87 octane E10, ever got the cars over 500 miles distance, despite 87 octane E10 being used most of the time.