Actually, I used to work at an oil refinery. We had two refineries (Phillips 66, where I worked and Valero which was about 45 min drive away from us) that sent fuel down in the same pipes to the same holding tanks for the rack (where trucks load fuel to deliver to fuel stations). So the fuel can be mixed with other refineries processed fuel. Many batches will be mixed in the same hide holding tanks as well. Also, the medium octane is mixed at the rack when trucks load up to deliver...taking low octane and high octane to make a medium octane. So again, different batches blended together to make the octane desired. Where the difference is, is the additives that each station/company requests. That's generally added at the rack as well. Some will ask for additives and some won't. And they have different additives to choose from according to what a company may specify or have created especially for them.
You can see a strong hint of that, at Shell stations here, there was a sign listing the ethanol percent, was as follows: Regular: 10% ethanol Mid-Grade: 5% ethanol High-Grade: ethanol-free I believe in the States they're all 10% though.
If your fuel has 10% ethanol in it & your gas sits in your tank for longer periods of time based on incredible gas mileage... Give great consideration to products like Sta-Bil 360 (#22264), a 10 oz bottle cost about $4.50 on Amazon & will last for about 5 tank fulls at ~2 oz per fill up. Use for Storage and will keep fuel fresh for up to 12 months Use at every fill-up Ultimate protection against Ethanol blended fuels and Non-Ethanol Fuels Help prevent corrosion above and below the fuel line, where no other additive can! Helps clean the fuel system to improve performance Help increase power and fuel efficiency For all gasoline engines, including 2-Cycle Use in your vehicles, motorcycles, small engines, generators Rob43
It is very rare to hear this key point mentioned, probably because so few people are aware of it. So many times you will hear someone say "My uncle knows someone who worked at a storage terminal and they told him that all of the trucks fill up from the same spout, so it doesn't matter what station you go to it's all the same gas". Being completely ignorant of the fact that the trucks get different additive packages depending on the brand. I used to hear a long time ago that some gas stations used no additives, but I think it was about twenty years ago that the EPA mandated the use of additives, and also the additives must meet a minimum requirement for reducing fuel injector and intake valve deposits. However there is still a difference as the cheaper stations are possibly using additive packages that only meet the minimum standard, whereas the major brands will use additives that exceed the minimum or even reach Top Tier level. Although you can't always go by price, here in Atlanta we have QuikTrip which is a discount gasoline chain located in twelve metro regions, mainly in the midwest and south, QuikTrip was one of the first first Top Tier certified gasolines in the country. And a few years ago Costco received Top Tier certification.
I can easily go 6-9 months on a single tank of gas based on my travel pattern and accessibility to charging stations but I don't like stale gas in my tank. Possibly cause more problems in the future if old gas is in the tank for too long of period. So my strategy is: 1) fill with highest octane available, and add-in fuel stabilizer 2) I set a reminder on my iphone every 3 months to start burning off the fuel, using HV-Power mode in B gear. 3) warm up the ICE periodically: a) during cold weather for heat b) warm up ICE before entering freeway on HV c) warm up ICE before depleting battery into HV mode
Oxidation and water contamination. Prime still has an fully functional ICE and all care/maintenance should be recognized with ICE. Along with flushing coolant, engine oil, transmission fluid change based on the time interval. Is The Gas In Your Car Too Old? - National Motorists Association
I think we have to go by Prime owners manual and any country-specific recommendations in there. We can also read the other PHEV manuals (Volt/etc.) to see if there is any second opinion among manufacturers. Then we as consumers are free to add additives like Stabil at our own risk and preference. Gaso tanks today go to great lengths to exclude air and water exposure, as well as prevent evap losses. So that is why Prime or PiP are mostly immune from the problems you might (and probably will) see in a lawnmower or gas can in the garage. bisco you are getting for your PiP EPA refomulated gasoline (clean) with additives, and you are probably getting Top Tier Gas with extra level of additives. So you have a certain high level of clean, E10 fuel. I do not know what John uses but probably not EPA reformulated gaso in his region. The Prime in Canada is in a whole different gaso recipe regime. In that case, higher octane probably means more additives and if Premium is used it might be E0.
Gen2 was the biggest problem, because what you do NOT want to do is run both gas and HV battery dry, and Gen2's logic allowed that to happen. Also you have to put a certain amount of gaso back in there (3+ gallons) for the system to see the gas in the tank.
Sttange, almost all my alerts this morning are "thread resurrection", ie: 2 year oldish threads brought back to life. Anyway: Why would you want to do that??
If the tank can be run dry and only filled up when one needs to? That way one would always have fresh fuel in the tank right?
Well sounds like you are in a Prime, and you need to follow the manual, and many posts here. But keeping your tank totally empty is probably not the recommended strategy. I do not know if long term dry tank could possibly lead to eventual problems with the highly complex tank system. I don't think you want to go there unless some here have blazed that trail. I am out of date if gaso sipping is needed by Prime for certain times to assist the battery operations.
Sometimes the Prime wants to run or warm up the engine even when you don't think you need it, so it will need gasoline for those occasions. I'm seeming to remember other conditions where gasoline is required -- it will continue driving in EV mode after fuel starvation, but will it start properly when it already knows the tank is empty?? -- but my memory can't dredge up specifics right now. Bob Wilson (@bwilson4web), who ran out-of-fuel tests on all his gasoline cars (when he still had them), could say more. Here is what Toyota says in its Prius Prime FAQ: