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Fuel indicator not showing correctly

5058 Views 4 Replies 2 Participants Last post by  Smitty
OK, this has happend twice to me now.

I have filled up in about 45 to 50 degree temp. Both times the fuel indicator has shown that I have already used "one bar" from the full line.

On this second tank the second bar disappeared at about 110 miles. (First bar never did come on)

Is it an air bubble maybe in the fuel bladder tank?
Is there a "Float" per se in the bladder like on normal tanked cars?

I always top off, (Yes I know your not suppose too) and put in almost another gallon when the pump first shuts off. So I know the bladder is full. I have always filled up this way.

On the first tank or first time it did this, the first bar was off and then about 2 days later it came on at about 60 miles into the tank, and stayed on until I reached about 110 miles.

Any suggestions?
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refilling after only one bar gone?

I seem to recall somewhere (I think the manual, but it's not handy at the moment for me to check) that the fuel gage may not register a gas fillup of less than 3 gallons... Perhaps this is your "problem"?
Nope, each time it has been 8 gallons or more when I fill up. I usually wait until I drive about 400 miles or more before filling up.

Smitty said:
Nope, each time it has been 8 gallons or more when I fill up. I usually wait until I drive about 400 miles or more before filling up.
On your first post, I thought that you said that you refil normally 1 bar from full. Since there are 10 bars on the fuel gauge, I assume that you either refill frequently (don't put much gas in), or that your gauge doesn't go lower than 9/10 Full.

On this post, you say that you drive about 400 miles before filling up, and put in ~8 or so gallons... Did you perhaps mean in your original post that you fill up 1 bar away from Empty?

If your comment is that your gas gauge doesn't seem linear (large variences in miles driven for each gas gauge tick to go away, say 100+ for the first bar, and only 20 miles for the last bar), then yeah, that's been seen before...
<shrug> I've even seen my gas gauge drop 2 bars from the time I turned it on in the morning to the time I get to my first intersection (less than a mile away). Don't know why...

My understanding is that the various fuel indicators are built into the bladder itself, which include things like the bladder knowing if it's on a hill or not. Lots of technology, but still not very accurate on the gas gauge itself. <shrug>

Just get to know your gauge.

(On my first car, the gas gauge would sit at Full for a VERY LONG time. Then it would slowly go down to half. I knew that if it got to Half, I had to refill fairly soon... Once the gauge hit half, it would VERY QUICKLY drop down to empty. It wasn't linear at all, but I knew how it worked, so I never had any problems. (Some people have reported that on their Prius gas gauge, the first 5 bars from full go rather slowly, but the last five bars (below half/above empty) go much faster...)
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ok Let me start over on this as there seems to be to much mis-understanding on the question.

First off I have had the car for over a year and am fully aware of how the gauge acts and responds.

I almost always fill up at about 400 or more miles into the tank. Any other time (When I fillup, wheather its cold or not) all the bars will light up to the full mark. And yes I usually get about 100 to 140 on the first bar before it disappears.

But, now to my original post, the last two times I have filled up the first light below the full line has either come on for just a short time, like 10 miles into the tank or not at all.

Since I have posted this question I have now put another 300 miles on the car and am now on the 4th bar. (Just above half mark).

This is inconsistant with the way it was performing in the past and was wondering if anyone else has had this problem.

The first time it did it, the first bar from full went out at about 10 miles and stayed that way until about 60 miles into the tank before turning on again and showing I was completely full. Then it shut off at its usual mileage of about 125 miles.

AS I said before I top off, and I know the tank is FULL to the brim. However, on this second time the first light never came on, and the second light turned off at about 140 miles into the tank. A bit short then usual. The second light usually shuts off about 180-200 miles.

My mileage still shows I am getting 54.6 mpg. Although when I do the miles/gallons it shows that I am getting around 50 mpg.

Hope this clears up my original post. Sorry for any misunderstandings.
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