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Here is some weirdness that I was wondering if anyone else has noticed or could explain. I took these photos the last time I went to the gas station. As you can see from the pictures, my historical mpg is 29.1 (the average since the last fill up was about 28.1). I had a range of 62 miles left, which would indicate just over 2 gallons left in the tank. As I've been taught to do, I filled the tank until the controller stopped the flow and did not top off the tank. I got 17.9 gallons into the tank, which would mean that I had 20 gallons in the tank. But it's a 22.2-gallon tank. Does the controller really switch off when there's still 2 gallons of air in the tank? I've noted this before, but this was the first time I got photographic evidence.
To make matters more interesting, after filling up it gives me a range of 535 miles. At an mpg of 29.1, that would give me 18.4 gallons in the tank. Conversely, 20 gallons at 29.1 miles per gallon would should give me a range of 582 miles.
Does anyone have any explanation for the discrepancies?
Yes. The answer here is that Toyota hybrid products are EXTREMELY conservative on these range estimates. On my Sienna hybrid I experience exactly the same as you, and on my mom's new Camry hybrid it is also the exact same. I have a friend with a Highlander hybrid, same thing.
My sienna will tell me 70 miles range, which at 35mpg I usually get around town is 2 gallons. 17.3 gallon tank. When I fill up, I'm lucky if it puts in 13 full gallons.
Similarly, I've run it down to 0 range previously where it just says "REFUEL" and then filled up, and put just shy of 15 gallons. That still leaves over 70 miles of driving before there is risk of having zero actual fuel.
I think they are just super conservative on these estimates as they don't want you running the tank dry, especially as you cannot restart the vehicle if you run out of fuel until you have replaced over 4 gallons of fuel (unlike ICE only vehicles where you could in theory restart vehicle with just 1 gallon to get to the next gas station).
Yes. The answer here is that Toyota hybrid products are EXTREMELY conservative on these range estimates. On my Sienna hybrid I experience exactly the same as you, and on my mom's new Camry hybrid it is also the exact same. I have a friend with a Highlander hybrid, same thing.
My sienna will tell me 70 miles range, which at 35mpg I usually get around town is 2 gallons. 17.3 gallon tank. When I fill up, I'm lucky if it puts in 13 full gallons.
Similarly, I've run it down to 0 range previously where it just says "REFUEL" and then filled up, and put just shy of 15 gallons. That still leaves over 70 miles of driving before there is risk of having zero actual fuel.
I think they are just super conservative on these estimates as they don't want you running the tank dry, especially as you cannot restart the vehicle if you run out of fuel until you have replaced over 4 gallons of fuel (unlike ICE only vehicles where you could in theory restart vehicle with just 1 gallon to get to the next gas station).
Now it's making sense! Thanks for the explanation!
@np20412 ”I think they are just super conservative on these estimates as they don't want you running the tank dry, especially as you cannot restart the vehicle if you run out of fuel until you have replaced over 4 gallons of fuel (unlike ICE only vehicles where you could in theory restart vehicle with just 1 gallon to get to the next gas station)”
Here is some weirdness that I was wondering if anyone else has noticed or could explain. I took these photos the last time I went to the gas station. As you can see from the pictures, my historical mpg is 29.1 (the average since the last fill up was about 28.1). I had a range of 62 miles left, which would indicate just over 2 gallons left in the tank. As I've been taught to do, I filled the tank until the controller stopped the flow and did not top off the tank. I got 17.9 gallons into the tank, which would mean that I had 20 gallons in the tank. But it's a 22.2-gallon tank. Does the controller really switch off when there's still 2 gallons of air in the tank? I've noted this before, but this was the first time I got photographic evidence.
To make matters more interesting, after filling up it gives me a range of 535 miles. At an mpg of 29.1, that would give me 18.4 gallons in the tank. Conversely, 20 gallons at 29.1 miles per gallon would should give me a range of 582 miles.
Does anyone have any explanation for the discrepancies?
Before fill-up.
17.9 gallons into the tank.
After fill-up.
There is about 2-3 gallons in reserve when the fuel gauge registers empty on modern Lexus and Toyota Cars. There is a lot of chatter on this on the 2nd Gen NX forum especially those with hybrids and plug in hybrids as they like to check fuel savings. That is how I learned of this on my NX450h+. The NX tank is 14.5 gallons and when the fuel guage said I had 3/10 of a tank left was expecting to fill the tank with 10 gallons of fuel expecting the tank but instead got 8 and 1/4 gallons. Then I learned there is 2.5 gallons in reserve on it that is not reflected in the fuel gauge. The reserve does two things, it is a safety buffer to keep the fuel pump cool and also a distance buffer. Back in grad school, I experienced clogged fuel injectors after letting my Acura run too empty and the dealer said most likely from sediments over the years and then running it to empty that one time did it. So now, I refuel my cars when I need about 10-11 gallons. So for my LC its about half way, for my IS its 1/4 left and my NX it is 1/8 left.
Weirdness at the gas pump
