2003 Odyssey gas indicator does not seem to be working accurately. Low gas indicator light was on, filled tank and it took about 6 gallons less than a normal empty tank fillup. After fillup indicator shows a half of tank.

1. Fill gas tank 2. Record odometer reading 3. Drive car as usual until 1/4 full. 4. Fill gas tank and record how many gallons it took to fill it again. 5. Record new odometer reading and subtract original reading. 6. Divide miles driven by gallons used.

mine did the same thing 2 years ago. i assume it is probably the fuel gauge sending unit in the fuel tank so i priced a new one. as i remember it was about 350.00 for just the part. my computer reads in gallons and is still accurate as to telling me how much fuel i have used so when i use 10 to 12 gallons out of the tank i fill it again. so far i have had no problem doing it like that. just don't run out of fuel because that is really bad for fuel pumps. mine has a 14 gallon tank so i make sure that i never go below 12 gallons used. i usually try to fill at 10 gallons used

The fuel pump is kept cool by the fuel in the tank. It is rare for a Toyota fuel pump to fail but if your running it that low on gas your not helping last any longer. I would suggest not letting your tank get below a quarter tank. That way you will never have to worry about whether or not the light will come on. Typical there would be about a gallon or less of fuel in the tank before the light would come on. If it did come on you would have about 20 miles r so of fuel left in the tank.

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One tank of gas is not enough to compare mileage. Or are you saying the computer's readout of mpg estimate is showing less? Try a tank or two of premium and see if that helps. Keep track of gas mileage. Driving techniques have a lot to do with gas mileage, as does long trips vs. short trips, highway cruising vs. city driving. For best mileage, do regular maintenance and keep the car in top running condition-good spark plugs and clean filters and clean oil ! Attend to minor problems before they escalate.
If you want to check actual miles per gallon, start with a full tank. Write the odometer reading down, and go. Everytime you put gas in, write down the amount. When you are close to 1,000 miles from the time you started, go fill the tank and include that amount of gas to your previous list. Now add up all the gas used and divide it into the miles to get miles per gallon. (976 miles/31.8 gallons = 30.69 mpg ) . Only one tank will skew your numbers, might be off cause the tank was filled more to the top than the previous fill-up. About a thousand miles of driving will give you a very accurate figure of miles per gallon for your car.

I would say between 1 and 2. Usually it is 2 gallons of gas, 40-50 miles worth.

I'm not sure I am understanding your question. The low Fuel indicator light comes on, depending on how sensitive it is set, when you have between 2 and 5 gallons of gas left in the tank. This also depends on how accurate your fuel level sending unit is reading the fuel level in the tank. The low fuel level light depends on the level of fuel in the tank itself but other than using that sensor it has nothing to do with the fuel gauge itself. The fuel gauge may or may not be accurately showing the fuel level.

the sender unit in the tank ,i think it has petrol in the float so its not reading correct.with the filler neck and associated pipes then it no doubt holds nearer 15 gals or about 80 litres .I couldnt afford to buy this much petrol in one go as its just over 1 euro 20cents a litre here so that would cost me 90+ euros or if the exchange rate is right this morning thats a dollar a litre

Hi:
I am pretty sure that the light comes on when you have approx 1/8 tank left. In my honda, with a 12 gallon tank, that equated out to 1.5 gallons, or approx 45 driving miles on flat land in the city. Of course, you should check your average miles per gallon with your driving style , as well as filling the tank once the light comes on, to see how many gallons are left, and you will have an accurate number!

The 99 expedition comes with a 26 gal tank as standard equip. and there is an optional 30 gal available. I suspect the gas pump you used is not accurate, and needs to be recalibrated. I think it's just a coincidence that the gauge is acting up now. Hopefully I'm wrong, and by some miracle you actually are now getting 300 miles on a half tank of gas! You may have a bad sending unit, this would result in inaccurate fuel tank readings.

this is caused by a defective gas gauage sending unit in the gas tank.