Gauge skipped last line

what was the guage reading before you filled? over or under a half tank. If over it won't reset. If under it should and if it doesn't in 4-5 miles I'd take it back to the dealer.

 

i dont really look at the bars that much other than to keep a vague track of how much miles i have left. i find the tank mileage to be a much better gauge and the reason is that the gauge isnt always consistent.

for a while i was tracking the mileage i got for each bar. i quickly abandoned that idea because

* i would gain or lose bars just from shutting off the car or restarting.

*mileage between bar changes varied as much as 200%.

*just like analog gas gauges, the bulk of the tank volume (about 60-65%) is measured by the first and last bars. iow, the middle 8 bars only account for about a third of the tank making the gauge very non linear.

in saying that, i found that using my lifetime average with the tank mileage, i can predict very accurately how much gas i have. although i have never gone that far, i am 100% confident that i can go 575 miles before refueling. that is more than enough for me.

 

I have not experienced any of the above problems. My gauge is not very accurate, but it is always pretty consistent, the biggest variable being how far I drive on the first bar (i.e. when the pump clicked off). Manufactured in December. SSC 40D performed not too many miles ago. Most gas added: 9 gallons, at 37 miles past the blink. ODO ~4500 miles.

But I appreciate the warnings, and if my tank miles ever get too high I'll know the gauge is probably off.

 

Delivery in May

I took delivery in May, Black #9. So far, my gauge has been consistant. I have all of my information tracked in a spreadsheet, My average fill up is 9.534785714. I have always driven until the last bar blinks, and have filled up anywhere between 1-24 miles after that.

After a fill up, it may take over 100 miles, sometimes 120 miles before I lose a bar. Each bar is about 50 gallons over all, but just like in my previous 4Runner, As the tank emptys, they gauge moves a little faster. In my 4Runner, I ususlly got about 300 miles per tank, I could go about 200 and it would show 1/2 tank, the last 1/2 I only got about 100. Most likely due to the shape of the tank.

Regardless, I would have my light on my 4Runner show up at different times. It would go off and on depending on the grade of the road. Personally, I feel the Prius is more accurate then the 4Runner was, plus I have more information to base how far I can push it. I feel comfortable that I can about 500 miles on a tank, before I need to be ready to look for a gas station. Even then, I feel confident that I can go another 25 miles after the guage begins to blink more than enough time to find fuel.

 

shape of the tank is fairly uniform.

the "flakiness" of the gauge has to do with the range of movement for the float that controls the gauge.

the tank has no room at the top for the float when the tank is full, therefore the float rides much lower (it is completely submerged) than it should when the tank is full causing an erroneous reading and the reason why a full tank stays full so long.

this also occurs at the bottom ot the tank when the float comes to rest on the bottom of the tank despite the fact that there is still several gallons left in the tank.

some vehicles experimented with weight sensors but it was discarded for some reason as they didnt work all that well either. (some of them would register a ½ a tank when the tank was actually empty. also the sensors constantly had to be re-calibrated)

 

Re: Delivery in May

I hardly think 9 decimal places of precision are meaningful there.

If each bar is 50 gallons, you've got a bigger tank than I have. But at only 100 miles for that first 50 gallons, you're getting only two miles per gallon.

I'd have my gauge re-calibrated if I was you.

 

I always try to fill up when I get down to 2 bars showing. I've sometimes had it take as much as 8.7 gallons to as little as 7.4 gallons. And I usually fill it up within a few miles of 2 bars showing up (20 max).

I've never let it go low enough to blink, but I'm thinking I may do it with this tank.