"miles to empty" sensor not working properly

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IamNick
Posts: 4
Joined: Fri Nov 27, 2009 4:36 am

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Not sure if I am characterizing this correctly--in any event, I have a 2010 FX 35. Ever since I purchased in 11/09, I noticed that the "miles to empty" reading will run itself down to about 30 miles and then blank out to two hash marks (on the dash) or two asterisks (on the console display). The low gas warning sensor will come on when my range is down to about 45 miles. The "miles to empty" will continue to decrease until it says 30 miles and then blank out as noted above. I brought it in today to the dealer to check this out and was told that this is normal operation. They said they have had other people complain about this but Infiniti has not indicated it is either a defect or a glitch and they do not have a fix for it. This reading makes little sense to me as I want to know how far I can go before needing to fill up again. The Lexus I had before this car as well as the Honda before that would both take the miles to empty reading down into the single digits. When I fill up after the low gas warning light comes on I normally get in the range of 21.8 to 21.9 gallons. Since the tank holds 23.8 gallons, I should have approximately two gallons in the tank. While I understand that the "miles to empty" calculation is based on the remaining gas in the tank and the current mileage, it would seem that there should be a sensor able to tell how much is left in the tank and based on the current driving conditions be able to tell me how far I can go until absolutely empty. Quite frankly, taking me down from 45 to 30 miles to empty and then blanking out is of little help. I would just as soon have had just the warning light and that's it.

Has anybody else had this problem/issue??


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Q451990
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Probably a CYA thing on Infiniti's part. Who wants to deal with an irate customer on the side of the road pointing to something on their dash yelling "but it says I have three miles before I have to get gas!"?

I don't think those trip computers were ever intended to be accurate down to the mile.

I'm not sure if the fuel pump design is the same on the newer FX, but on the older Q45s, keeping at least 1/4 of a tank helps cool the submersable fuel pump and extends it's lifespan. Not to mention you're less likely to be sucking up the bitter dregs of debris on the bottom of the tank.

Heath

fixer
Posts: 99
Joined: Thu Jun 05, 2008 11:59 am
Car: 08 Sentra

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the fuel tank on an fx is a horseshoe style, meaning there are two tanks on either side of the driveshaft, you also have two separae fuel sending units. the actual fuel gauge reading is an average of both sending units in series. the total ohms of both sending units is converted to a fuel gauge reading, you may have a problem with one of your sending units going shorted when about empty causing the double dashes. does your gauge reading change when you get the dashes or is it already too low to read?nyway, the miles to empty is a calculated amount that the computer displays after trying to decifer the signal it is getting from both sending units. I would recommend replacing both sending units to be sure. but i would not trust the miles to empty .

simlam
Posts: 7
Joined: Tue Feb 09, 2010 10:58 am
Car: Ex35

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I have the EX35 and have to same problem as IamNick.

The "miles to empty" alert would turn with around 70km left....and turn blank around 40km.....which defeats the purpose of the "miles to empty" warning.....


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