Any Idea of how many gallons I show truly be putting in my 2009 Prius after two bars left? I bought this car used off the lot with 160k miles on it last month. Never been in an accident. just general maintenance and oil changes. I don't know what it is as I seem to burn through fuel quickly each week but I don't even know if I'm even putting enough in the tank. I hypermile by pulse, coasting and gliding getting the average up to 50-66 MPG but seem to get only 200 miles out of it and back at the pump again. Some weeks I put $10 worth of gas after two bars left, another week $15 with two bars left and another week $6 of gas with two bars left. The gas gauge all ways shows all full 10 bars no matter how much I spend on gas. I heard the that bladder is an issue.
welcome! you're correct about the bladder. just fill to the first click and keep a running average of your calculated mpg's. you can try waiting a minute after removing the gas cap, pumping as slowly as possible, holding the pump handle upside down or 90 degrees, and trying different pumps. if you go 200 miles at 50 mpg, you should be putting 4 gallons back in, right? but only if you started from full.
Thanks for the response! Yeah but I seem to fill up every week rather than every too weeks. I seem to burn the gas very quickly even blew though 200 miles already on two bars. I though we supposed to be getting 500 per full tank? Something doesn't seem right especially when I'm using the pulse, Coast gliding.
went from a full tank of 10 bars from Sunday the 21st to now only two bars left on my gas gauge. I paid $10 in gas on Sunday. This is me coasting the streets tonight very late when very little to no traffic. I shouldn't be burning through my gas that fast after putting $10 into the tank from 2 bars. Posted via the PriusChat mobile app.
Take bisco's advice. Just fill the tank till the pump shuts off, reset the tripmeter, and note the odometer as well. Go through that tank, as low as you feel comfortable, refill the same way, reset the tripmeter after noting, note the odometer, do the math for the miles per gallon, report back.
^^^ they realized the error of their way and engineered a way around it. probably cost 'em a few shekels.
o/p, the bars and the dollars and the amount of miles on a tank and the weeks between fill ups mean absolutely nothing. you have to do the math. it's painful, but like they used to tell me in school, someday it will pay off.
The 2004-2009 Prius have a flexible rubber bladder inside the metal fuel tank that was used for emissions purposes (Toyota has since moved to a pressurized tank). That rubber bladder led to some uncertainty in the amount of fuel left in the tank.
In my region, $10 of gas is less than 4 gallons. 200 miles is quite reasonable for that amount. Plenty to traditional cars won't get 100 miles for that price. Those traditional cars will also swallow up $25-40 per 'tank' of fuel. Your car is suffering from a small/weak bladder, but is doing just fine on MPG.
Thanks everyone! Looks like the gas i burned through appears to be normal then as it looks like I'm just not putting in enough gas to 11.9 full. So i guess my issue is What's strange is I even put $6 worth a gas that's 2.19 where I live at roughly 3 gallons in when I fill from two pips, the gas gauge has a tendency to say it's full with all 10 bars which is probably why its throwing me off for my gauge to drop from 10 pips fast in 3 days to only two left. Is that even normal? Because that's not even a full 11.9 tank. Any idea's of how many gallons left with two pips? But not sure how would i trust something that guess what I'm pouring into the tank because of the bladder. I'm so use to linear gas gauges. Posted via the PriusChat mobile app.
It varies from car-to-car so the best way is to keep track of how much you put in to a full tank and that can at least give you a ballpark range. I know it's not the answer you're looking for. It was easier when the cars were new but as the car ages and the rubber ages, the variability increases.
Just an error. I did this enitre post with a smartphone. But doesn't really matter though as I'm good as though something was odd for a minute as I got my answers. Other than that, the car runs great as new in mint condition. Posted via the PriusChat mobile app.
uncertainty, that's a funny way to put it. My favorite "uncertainty" was filling the tank with a slightly acting-up fuel nozzle. You realize it's got to be full, you pull the nozzle out, and it vomits up a good half gallon or more. Good thing you're not smoking. .
I have tracked a total of 10 tanks on Gen4 and 2 on Gen3 (as I had come to the idea of doing only a couple of months before selling it...). I wrote down every so many traveled km, the DTE and the km driven so far with the tank and its related fuel consumption value. I then calculated how many total km the MFD had been estimating at that point (i.e. current traveled km from tank + DTE estimated km) and recalculated the fuel equivalent fuel consumption, by not considering the fuel light fuel level, as per user manual (6.4L // 1.69 US gal). As I result, I have found out that my Gen4 is overestimating range on average by 20%, and taking into account the fact that the MFD overestimates by about 4-5% in Gen4, this values lowers to 13%. Otherwise said, whatever the DTE says, take 20% off and you know more or less when it will reach zero in real driven km. I have noticed that the fuel light comes on typically at 50km // 30mi DTE. When DTE is at 0, and the fuel bar is totally empty, I still have about 5L // 1.3 US gal in the tank.... Gen3 was on average (albeit calculated over only 2 tanks) 22% off. All in all, I really don't rely on the DTE indication but simply use on the amount of km driven so far, the (corrected) fuel consumption for the tank, and calculate, based on these values, how many liters I have used, that is, how many I have left in the tank. I then use an average fuel consumption of choice, typically 5L/100 // 47 mpg (I am being conservative, in a way), to estimate how much left I have, before being forced to walk. I have printed a table that I simply look up, to avoid calculations on my phone while driving (unsafe!). A 20% off DTE estimation, is not too shabby. But DTE/fuel light/fuel bar are in general so conservative, that I never really rely on neither of them to know when to fuel up again (which is essentially based on logistics and "strategic planning" ).
I think if you fill at half tank, DTE gets even more inaccurate. IT appears to assume the miles between full-ups are for a whole tank, not what was just added.
