I just got my Prius on Sunday and I am watching the miles to go or miles till I have to fill up meter. I am noticing it is decreasing faster than I am driving. Is that normal? Does it decrease faster depending on how you drive and not necessarily how many miles you have left?
How many miles you have left and how you drive are directly related. That is, the better your mileage the more miles you can travel on the fuel left in tank. The miles to go indication goes back some amount of miles and uses that fuel mileage and the fuel remaining to determine how far you can go. If you get worse or better mileage than you have been getting it will be off of course. The indication also gives you some room for error, mine usually is at 0 miles to go when the last pip on the gas gauge starts to blink. This usually means there is about 2 gallons left in the tank.
gen II does not have it, (at least my pkg.) but our 08 hycam does and it's always short. plus, i don't think it counts the 2 gallons after the low fuel light comes on.
mine tells me i'm out of miles when i fill up. but i only put 8.6-9.5g in when i fill. so clearly i'm not out of fuel. i don't use it. i just use the fuel guage and fill up when it flashes.
Mine seems to give around a 2.5 gallon reserve. Miles to empty + 100 should be close to accurate, but it's better to have some reserve than to run out of gas. Also if I'm taking short trips the miles drop quickly, so check it again after your down half a tank. When I'm in the city, I'll fill up at the next convenient time after the flash which may be 50 miles later. If I'm driving out in the middle of nowhere I'm much more conservative. But in the middle of nowhere I get better mileage ;-)
Everyone else's experiences are interesting to me because I don't even switch over to my 'Miles to Go' display until after the last bar begins to blink and then it always shows 30 - 40 miles to go, which is indicative of having about one gallon of gas. I had a strange experience once where it skipped from 30 + miles to 12 miles in the blink of an eye but otherwise it has been pretty reliable. Actually it's one of my favorite electronic features.
I once mentioned this Because the car seems to consider the tank empty when it still has a gallon or two the miles driven + miles to go gets lower during the tank assuming pretty steady MPG
There have been a few times on my Gen III that I only put 2-3 gallons in when there are 1-2 bars left. This does not seem to affect the value of the "miles to go" meter. In fact that value can go to "0" and there are still bars left on the fuel guage after that partial fill-up. It takes a fill-up to top off the tank in order to reset the "miles to go" meter so that it shows the correct value. Does anyone know how much gas needs to be put in the tank before it can affect a change in that "miles to go" value? To me, that miles-left value is useless unless you put enough gas into the tank to fill it.
lonestar: Not sure but an educated guess would be at least 2-3 gallons. Guys, of course the DTE isn't until the last drop. Can you imagine the lawsuits if it said 5 miles left and you were left stranded? The DTE will always indicate the distance left to the reserve (i.e. the low fuel light). It'll almost never be on the dot but it can get fairly close. (Think about it, it's pretty hard when the car doesn't know what type of driving you're gonna be doing).
The only thing that the Owner's Manual says is: When only a small amount of fuel is added to the tank, the display may not be updated. I read somewhere on here where you need to add at least a half of a tank before the DTE will reset. I think people are trying to read way too much in to this DTE. It should be for a basic indication only. As stated by Tideland Prius, this is the distance to the reserve when the low fuel flashing light begins. If you are going to push your car so close to empty, I think Toyota is going to let you go this on your own !
The (european) owners manual says that, when it indicates 0 km to go, there should be about 6 liters left or 1.6 gallons. I think this is too much: you can still drive one hundred km's (60 miles) ! The Gen II would then give you a clear warning to find a pumpstation as soon as possible. Not so with the Gen III: it simply stops. Out-of-gas never happened to me with my previous 2004, but now... alas.
This has not been my experience. If by 'low fuel light' you mean the blinking fuel bar, mine always has 30-40 miles left on the 'Miles to Go' meter when the blinking starts. Or, am I misunderstanding what you mean?
The miles to go tank on my TCH & 10 Prius is pretty much useless IMO, I just go by the avg mpg and minus 1-2mpgs and the blinking indicator. On my 09 Acura TSX OTOH, the miles to empty indicator actually fluctuates back and forth depending on the MPG which was a nice surprise and was pretty accurate when it came to filling up. If only it did that with the Toyotas...
The problem I see is that my work is only a 10 mile round trip and lets say for example my miles to go meter or empty gauge says I have 400 miles left. Well after my 10 mile round trip it will say 360 miles to go. What I don't get is I went 10 miles for the day but instead of the meter decreasing by 10 miles it decreased by 40. So, is the meter really based on how you drive and how much fuel is being used rather than just counting down miles? Is that normal?
It is trying to estimate based on your MPG and miles driven. If you have been averaging say 50 mpg and then on your last trip you have a lot of stop and go driving and your mpg drops to 30 mpg. It is going to adjust based on this last mpg. So there will be a big difference between your previous trips and this last trip.
