Ok, so I've done about 400miles and have 4 bars left on the fuel gauge. I do about 30 miles a day. When do I know when to fuel? 1 bar? Also, I will put in premium (or whatever is the most expensive). I know a couple of years ago, Shell had pollutants in their premium gas which caused engine failure and Shell had to pay for the engine cleaning etc. Is there a brand you prefer?
I usually fuel up at 2 bars (3 if I know I'm going a longer distance than normal commuting, like before a weekend). There are other threads you can find where people try to estimate the amount left in the tank when the last bar starts flashing, it's more than a gallon but less than two as I recall. The owner's manual states you should use regular (87 octane) gas; there's no benefit to using premium and you will just be spending extra money. There's no fuel mileage reason to use other than regular, and the ICE is not a high-performance tuned engine that needs premium to deliver more power. My wife and I always use BP, that's more because we have BP credit cards that give more of a rebate at BP stations than for any other reason. Any major brand should do.
If you really feel like throwing your money away for Premium gas, PM me and I will send you my PO Box so you can send it to me. Premium gas is higher octane gas that is only needed for engines that are designed for it. It will not do your car any harm, but it will not do you the slightest bit of good. That is a fact that you can look up as many times as you want, not only on the internet but even in real books. If you lived near Port Everglades, which is south of Fort Lauderdale, you would see the tanker trucks pulling up to the large tanks where gas is stored when it gets here from the refinery (I am pretty sure there are no refineries in South Florida). The trucks all line up and fill up at the various places with apparently no order or distinction. I am convinced to a moral certainty that there is little or no difference between most gas that is sold in gas stations. Some brands add certain additives. Maybe they do that in the storage tank, but if they do, then whoever bought gas from them gets the same additive. Maybe some of them add it in the trucks. Don't know and don't care. I would try to buy gas at places that seem busy so that the gas doesn't sit in their tanks a long time, but other than that, I buy wherever they take credit cards and don't gouge me for the privilege and I don't buy Citgo because it is Venezuelan and I don't buy from people who hate me. Otherwise, who has the best price gets my business. I also own a Ford retro Thunderbird and I am sure we will get some of the same posts I read on their forum: "Nothing but the best for my (fill in the cute name)!" "I buy premium and I pay the top dollar for it. I don't care if they say 91 octane (for the TBird), I buy 93 octane!" "I buy Nitrogen for my tires because my baby deserves the best!" As far as when to fill up? When is it convenient? There is no benefit to letting the gas get really, really low and there is a decided problem possible if you happen to run out of gas. Besides, if your tank is almost empty you have more chance for condensation which will introduce water into your fuel system which can be a problem. I fill it up whenever I am not in a hurry and am below a half tank. They don't give a quantity discount at the gas stations, do they?
Don't waste your money on premium--the owners manual says to use regular. Regarding brand, Toyota and other manufacturers recommend Top Tier gas brands: Top Tier Gasoline Most gas sold in the US is basically the same, except for the proprietary additives each gas company uses. I primarily use Chevron (which contains Techron), but also use Shell and 76 on occasion, and if I need a fill up when I'm near a Costco, will fill up there. When to fill up? When you're getting low and it's convenient.
I'm surprised Mobil is not on there, although we primarily fill up at Costco. Anybody knows where Costco get their gas?
I fill up at Costco, Arco, 76, Mobil.... whatever is cheap (87 octane) and close by me at the time I need to fill up. I always drive until the car starts to beep (last bar flashing) and my "miles to drive" reads 0 miles.
I believe there's a Toyota TSB for the second-generation car (2004-2009 model years in the US) that reports poor running when using higher-octane fuels. My car can sound a bit dieselly at times - in Britain 'Premium' fuel (95 RON) is the lowest available. (There are two main ways of establishing an octane number that result in two numbers - Research Octane Number, RON, and Motor Octane Number, MON. The figure on US gas pumps - Anti-Knock Index or AKI - is the average of the two. RON is about 8-10 higher than MON for most fuel meeting the appropriate standards, so RON is 4-5 higher than the AKI. That makes 95 RON roughly 90-91 AKI.) I use BP because the BP station closest to me is equal lowest in price with Esso (Tesco Express). The nearest large supermarket is a way away and the car really did run better - in my view - on BP than on Tesco own-brand. I refill shortly after the fuel level has dropped from three to two bars, so there's about 25% left in the tank. I usually fill about 35 litres; the tank capacity is officially 45 L. The fuel pump is cooled and lubricated by the pool of fuel in the tank and you're recommended to refuel at about 25%.
Like SDM44, I usually fill up when the DTE is at 0. Filling up is 15 minutes I'd rather spend doing something else so I fill up only when I have to.
'Only' regular gas will go in Pearl when she needs her first tank of gas. We have a Harps grocery store and 'can't remember the name' gas station that has lousy access nearby. The are in a constant price war, so they are always the cheapest around and I fill at Harps. However, we also have the supercharged Mini that requires premium for full performance (as noted in the owners manual) and has a sensor that determines octane and adjusts timing and therefore horsepower. I always know when my wife has pumped regular gas as the engine performance is radically different.
I buy my gas based on this evil ranking: SOCIAL RESPONSIBILITY RANKINGS FOR GAS STATIONS to me, saving $1 on a tank of gas is not so important. Based on the above ranking, I buy Shell, We don't have Sunoco or BP in my area and I Won't buy venezuelan (valero, Citgo etc.)
And what additional useful information did you bring to this conversation? Additionally, if I'm too mentally challenged to "get it" maybe someone else would find your point of view enlightening.
This thread may also be of interest: http://priuschat.com/forums/gen-iii-2010-prius-fuel-economy/79125-brand-gas-mpg.html
I have to record the numbers from the HSI for my records but what takes most of the time is the topping off as I like to truly fill up. I never do it though and drive home and park it due to possible expansion concerns. I fill up on the way somewhere so I immediately start burning some of it off.
But you're saturating and damaging the car's emissions/vapor collection system by continuing to fill up after each top off.