2 bars to out of gas in <5 Miles!

Well at 51mpg you are pushing it with 475 milers on the trip I think so I would say just fill up at no less than the 1/4 tank mark. On most American cars you shouldnt run the tank so low anyway due to cooling issues with the fuel pump and the likelyhood of pisking up more junk from the bottom of the tank. Not 100% sure how the Prius works but its a decent policy to go by.

 

That really sucks.

 

Was this with the new 2007 or the 2005?

Tom

 

<div class='quotetop'>QUOTE(qbee42 @ Oct 23 2006, 08:58 AM) [snapback]336689[/snapback]</div>

I think it would have been the 2007, its only the second tank of gas.

It took my 2006 about 5000 miles for the fuel gauge, MFD and actual usage to balance out. The most I've ever gone on a tank of gas is about 470 miles but that was after my readings stabilized.

 

Filling up at 1/4 tank would be better if I had about 3 or 4 more gallons to work with. As is, I seemingly stop for gas way too much.

In the summer, I could easily hit 550 miles between fillups which is 4 days round trip to work/home with a side trip here or there. Now that it's cooled off, I'm just getting into blinking territory as I get to the 530 mark. Well, 530 is door to door to work and back for 4 days with no side trips. It's the difference of 2 or 3 mpg over 10 gallons.

I haven't run out yet, but it sure make you drive lighter on that last leg toward the desired fuel stop when you are hoping you make it as far as possible before you get the last bar, then as far as possible before it starts to blink, then when it does, you are only 5 miles from the fuel stop, so you are really hoping that you at least get within 3/4 mile or so before it quits so that you can hopefully make it to the pump on battery if needed.

So far, I've only done the blinking pip thing about 7 times. I guess if I had 13 useable gallons I'd just set myself for wishing for 680 miles rather than just wishing for a solid 530 between fillups.

Going 4 days between fillups is bigger than you might think. Seems like you spend your life at the pump filling up every third day.

That was my big arguement against the 1/4 tank fillup thing. If you only fill up every month or two, then why not fill up at 1/2 or 1/4...

I wish there was a reasonably priced mod to get me about 2 gallons more per fillup. I'd trade my current prius and pay $300 upcharge for the optional 16 gallon gas tank.

 

Also take into account any differences in inclination - i'm not sure if it happens with the Prius too, but my old car used to have wild swings in the needle when going up and down hills when it was low on gas.

I'd say this is definately worrysome, and i would take some extra care over the next couple of weeks to ensure that the fuel gauge is correct (ie record the amount you put in the tank and compare that with your mileage to see if you're getting much lower than the gauge says you are)... i know, i know, this type of obsessive record keeping is generally considered bad, but thats just because people try to use it to justify driving with a blinking pip... if you use it to justify stopping early, however, i think it's fine.

Of course, if you keep encountering problems like this, get the tank somewhat low (to the point where you think this sort of this will happen in the next 5-10 miles, based on records) and take your friendly local prius tech out for a little drive to demonstrate the problem.

 

If this is your new car with only 2 tanks experience, then I'd say the gauge needs the calibration procedure.
I go down to 1 bar regularly and if I ran out I'd get it fixed or junk the car. Once it starts flashing I consider it OK to run out.

Any quick jump down in fuel level means the gauge is lost and is not measuring anything useful.

The calibration procedure is here:


http://priuschat.com/index.php?showtopic=1...and,calibration

 

I guess you must be used to driving fuel efficient cars then. Most of my vehicles never got more than 320 miles to a tank so stopping for gas every 3rd day or so was just nomral life for me so its easy to fill up once a week in the Prius.

I'll say I wasn't bashing in this at all so don't get on me about that. He asked for a solution and I offered simple advice.

 

Good to hear it wasnt in a really bad sopt that this happened. Imagine running out in a storm or with a baby in the car in the Mohave in summer or something. Yikes.

 

wow man that really sucks. but i will say that in my experience, the gauge is not as accurate when at highway speeds. case in point.

for nearly 3 months, i tracked when each bar disappeared (this was before CANVIEW) and noticed on 3 different occasions that when at freeway speeds for extended periods of time, bars seem to not disappear as they should.

instead of a bar disappearing on a somewhat predictable schedule, they would disappear in clumps. having two disappear in 10 miles etc, albeit, nothing nearly as drastic as your situation, but nonetheless still very unpredictable.

i had a few situations where bars would disappear overnight after a trip of at least 100 miles. never saw this happen with short trips. so got me thinking that maybe a vacuum situation happens when gas is consumed at a certain rate.

wouldnt think that this was the case since any vacuum would be very detremental to the fuel pump. but imagine a vaccum being created that might cause the bladder to tighten up in the vertical plane (opps wait 2007... no bladder??) causing extra bars to display. vacuum is released, the bag relaxes, the gas gauge rapidly loses a few bars.

then again.... have been watching a lot of 911 conspiracy shows and it has gotten me to be suspious of everything...

 

<div class='quotetop'>QUOTE(F8L @ Oct 23 2006, 12:07 AM) [snapback]336626[/snapback]</div>

2 bars is 1/4 tank right? True, we had been on 2 bars for a while, but we felt it would be ok to wait until 1 bar based on experience with the '05. We had just passed an exit when it dropped to one bar. It was 11 miles to the next exit so we weren't worried. About a minute after that, the low fuel message flashed and beeped and we said "Wth? Guess we better stop at the next exit for sure then." But then within another couple minutes, we were completely out of gas. We coasted as far as possible in the emergency lane and ran the battery down to two bars and ended up about 2 miles from the exit.

 

why not just take it to the dealer to reset the inclinometer? if you tell them your gas gauge went from 2 bars to out of gas in 5 minutes... one of the first things they should be doing is resetting that. you can also request that they try this first.

 

<div class='quotetop'>QUOTE(DaveinOlyWA @ Oct 23 2006, 07:42 PM) [snapback]337104[/snapback]</div>

I've tracked when the bars disappear as well (use the 'B' trip odometer) - no canview for the '06, AFAIK. It isn't real consistent as you say, but then I haven't taken many long trips, it's mostly short stuff so the differences are fairly minor in my experience (<20% variation in mileage per pip within one tank). I've noticed some changes in temperatures will affect how fast it runs out (if it warms up, things expand and you get great mileage for that pip).

BTW, there's 10 pips in the fuel gauge graph, so 2.5 (if it existed) is 1/4 tank.

Dave - weren't you the one that needed to go a bunch of clicks to fill up your tank? I'm wondering if there's some kind of anomoly in your tank, a funny bulge or something. This might be the case for the OP as well, although it's unlikely - some object lying on the bottom of the tank could cause it to show a high volume of gas when there's really not that much there. But I like your idea of vacuum (or pressure) building up on a long drive, causing the gauge to not drop when it should until there's enough pressure difference it starts to equalize and suddenly the gauge starts moving again. I think the problem isn't why did it drop so fast, but why didn't it drop sooner and give proper warning.

<div class='quotetop'>QUOTE(daronspicher @ Oct 23 2006, 08:33 AM)</div>

Not many cars get you >500 miles on a tank, not sure what you're used to. Never heard of an upgrade for a gas tank either, altho you could carry a plastic 1-gallon container in the back for emergencies, if it doesn't give off fumes. Most people (thankfully) don't live 65 miles from work either. I understand your frustration, but it comes from the extra-long commute, it's not a fault with the car.

 

well, no actually, i dont have the patience for a bunch of clicks to be honest with ya.

i will say that during the time i was tracking bars, in an effort to get more consistant test conditions, i did keep in mind the amount of gas that was used when filling and if i was more than a ½ gal short or so, i would put in a little extra, but i usually go to the nearest quarter or so and stop after the first click.

 

<div class='quotetop'>QUOTE(Cheap! @ Oct 24 2006, 10:48 AM) [snapback]337416[/snapback]</div>

sorry wrong response to wrong thread.