Prius's MPG is not accurate

I know I'm new here but I am not new to cars, and I have never owned a car that had a gas gauge that was accurate below a quarter tank. My Prius gauge is as accurate as any other. My Wife’s Town & Country is off by at least 5 to 10% on both the MPG and miles to empty.

The point of my post was twofold, one to let people (that want to push their luck) about a cardboard gas can that I keep in my cars for emergencies. It's called a Gas-o-Haul (I don't want to post a link because I'm not sure of the rules on doing that) you can Google it and find it for sale at many places. It's a collapsible gas can that folds flat and hides well without taking up space.

The other point is off topic. While this is just an observation from a new member, I have never seen a car site where more people put so much effort into putting other people down for not agreeing with them. Maybe I need to spend more time on here, but it seems that by the second page of every thread someone on here is putting down someone else just because they have different ideas.

Be Safe.

 

LOL. I agree, but you'll probably get flamed for THAT.

 

You gotta be a fool for saying something so preposterous!

Actually, this site is pretty civil compared to some I've been on. The vast majority of PC members are respectful even in disagreement. It's a very small minority that routinely seeks to put others down.

Howdy, BTW, from a few miles to your west.

 

I asked the question in another thread, "has anyone ever run out of fuel with 2 bars on the fuel gauge?" No one said they had so I don't see a problem. With 2 bars you can expect to have something less than 20% left in the tank, that is like the reserve on a motorbike so it's time to look for fuel. It really isn't that hard.
Fuel gauges are an indicator, not really an accurate gauge. Most cars will use more than 1/4 of the tank before they read 3/4 full, most people can cope with this. I just know as my gauge has less illuminated bars the fuel tank has less fuel in it.

I don't think the gauge matters much on a trip where it's a long way between fuel, you need to plan your journey like in any other car to refuel before you run out. If you assume you have 40 litres in the tank when full and you use about 5.2L/100km you know you need to plan a stop for fuel within 760km so you can look at a map of your journey and work out where you will stop for your next fuel before you head off, maybe for safety within 700km. Not really that hard is it?

Good thing about the Prius is you can go further between fills so you can stop further away, cool eh?

If I drive from Adelaide to Melbourne(738km) for example I know I can get all the way in my Prius without filling up but if I take the RAV4 I wont, so I fill up at Nhill where fuel prices are reasonable even though I will still have half a tank left or I can go on to Ararat and fill up with a 1/4 tank left.

If I want to drive Adelaide to Sydney(1400km) I will need to fill the Prius on the way so I'll stop at Mildura where prices are reasonable then I might fill at Narrandera before I get to Sydney and both these places have lots of good Motels where I could stop for the night. I worked this out without a fuel gauge to look at, and I'll not stress about running out, not hard at all.

What did you have in mind that needs a super accurate fuel gauge?

 

Then fill up your car before starting your trip. The Prius' range is easily 200 miles more than the distance between these two cities.

 

That is only 432km or about 270km under a tank with fuel to spare.

 

You have found one of the Prius problem items. The gas gauge is very non-linear. Two bars can mean 2 gallons or 2 pints....usually closer to 2 pints. I have not heard of running out of gas with two bars showing. I have heard many run out of gas very shortly after the two bars were on only for a few miles before they went out.

This misleading behavior is a result of a fuel bladder being used instead of the conventional fuel tank. The idea that 1 bar equals 1 gallon is true for only one of the middle bars. The top bar is equal to about 2 gallons. The bottom bar is equal to a lot less than 1 gallon....as many have proven.

 

After reading this entire thread it occurs to me that Toyota must have designed the inaccuracies into the fuel gauge so that Prius owners would have something to complain about. If this is the only problem you have with your car that says a lot about Prius quality

 

Because, even in a Prius, two gallons are not going to get you from Los Angeles to Las Vegas. Wasn't your complaint that you did not want to pay exorbitantly high gas prices in the middle of the desert?

 

You got me, I can't amswer that except with another question, do you want to run out of petrol or get where you are going?
Also the answer was in the rest of my post. Even if I have 3/4 of a tank I always fill up before a long trip before I leave town. I also hate paying high desert prices for petrol.

I'm going to assume you never charge your mobile phone until it is down to 1 bar also and I'm also going to guess you are often caught with a flat phone battery.

From 10x MPG doesn't work for me

 

wow another gas gauge complaint thread... ya have been many here that's fer sure.

i dont see the issues to be honest with ya. when the last bar blinks, there is about an 8th of a tank. that equates to near 1½ gallons.

i have a Corolla with the old style (just as inaccurate) analog gauge that did what most did. it went to empty and beyond... but i didnt consider it accurate since the "add fuel" light came on about the same place... just at an 8th of a tank... sometimes as early as a ¼.

but being analog...i ignored it because i could see that i had plenty of room until empty where i would start on the reserve...

so i have to ask... is your complaint about the accuracy of the tank? or is it that lack of warning when the tank is "really" close to empty?

i find it unusual that many here "claim" they knew how accurate their gas gauges were on their previous cars when they did not have an MFD to report the mileage the car thought it was getting so there is no other comparison. i also found that very few really tracked their mileage to even a fraction of the fervor that they track mileage now (heck gas was 40 cents a gallon, the paper to track the numbers cost more!!)

now i will say i did track gas mileage occasionally. long trips, have done probably close to 100 trips of a 1000 miles or more in my lifetime and most of the time, i tracked gas mileage on those...but mostly because it was easy to do.

but like i say...not that worried about the bottom of the tank i guess.

 

Sorry, I don't take "Highly Suggest"ions from a new poster that hasn't established himself nor taken the time to list what year/model Prius he/she drives, or where they're from. You can do your own demanding.

As already mentioned, there are threads on PC that discuss the problems you bring up. Probably every car I've owned has had something that could have been made better. The gas gauge on the Prius is not a deal breaker for me, at least it hasn't been for the 27K+ miles driven so far. We all have different expectations when we buy a vehicle. I hope you can learn to deal with the gas gauge so you will not let it keep you from enjoying the rest of the car.

 

Yeah. I didn't even know I HAD an issue with the gauge until I got on PC. We routinely run it down to one bar. Is this possibly more of an issue with earlier models?

 

No, I think it is to do with the digital nature of the gauge not behaving like an analog gauge people are used to. And people think if they get 10 extra miles from a tank that somehow improves their overall mileage and they use less fuel. Go figure.

 

The MPG calculation is quite accurate. For the last 3 years, I have logged my odometer, gas purchases, and MPG readout and mileage reading from the MFD when I purchase gas. On my 2004 Prius, the readout automatically resets, although not immediately, when the tank is filled (assuming a 'significant amount' of gas is added). Anyway, for 2005, the MFD was about 3% high; for 2006 and 2007, the difference was under 2%. I've posted these data to the Priuschat Fuel Economy forum, with each year's post also referencing the previous year's post. I've just posted the 2007 results here.

 

Re: Gas gage not accurate -- Toyota Support agrees

You'll only get a recall for ANY car via the government if it presents a safety issue or is somehow non-compliant w/Federal motor safety vehicle standards.

 

No thanks, My car doesn't need fixing. So far my Prius delivers beyond what's advertised, I get a consistent 60 MPG or better, at least 600 miles between fill-ups, and I always know how much gas is going to go into the fuel tank.

 

Amen brother, Driving 40 years and repaired 60 cars a month. NO GAS GAUGE IS ACCURATE. Just keep a log of useage and mileage to be accurate..

 

And then don't try to estimate from those records how much driving range remains. Anyone who does that while ignoring the flashing of the last pip will eventually run out of gas.