Here in the USA, gas brands are all dump their raw gas that goes into a common pipeline all over the country
It is the supplier who delivers to the gas stations that adds the amount of Ethanol and cleaners
Many are crooks who are for high profits so since the Ethanol is cheaper, what this pump into the stations
underground tanks, instead of like E10, could be E15 or more
If in doubt what you're really getting from a station is a quick test
Being Ethanol attracts water as an example test
You can either buy a test bottle like this or you could make one
Add water to the blue line, since water is heaver it will fall to the bottom
Then fill with the gas, shake it a bit and let it stand a few minutes
ANY water in that gas will then fall to the bottom and raise the water line
So you know that exactly how much Ethanol percent you're pumping into your gas tank
View attachment 21539
Since water drops to the bottom of your gas tank, and you use no product to dry that out
over time there will be a lot of water in the tank, so best not to run the engine with 1/4 tank or less.
The same happens with gas stations, here they are supposed to keep their tank clean and purge out water
IF not doing that, then that water also is being pumped into your tank