legrunt

For me, about 80-100 km.

15RC350F

I have recently driven, inadvertently, pretty close to empty. In this case I put in 14.605 gallons of fuel (reminder: the tank is officially 14.8 gal) and was about 35 miles or so beyond the warning.

jim256

Actually its 15.9 gal. (60 L, 13.2 Imp.gal.)

15RC350F

Thanks for the correction; I was looking at the specs for the 2016 Lexus NX 300h!

Purebeard

I never bring to this situation, when the bulb lights up, it's bad for a car and can fail the fuel pump.

philwojo

Totally, 100%, disagree, it is not BAD for the car in any way and it won't fail the fuel pump. I am not sure where you got that information but it is totally incorrect and wrong.

Toyota/Lexus always seems to error on the side of caution, they are notorious for also not having accurate speed displays either, they are always slow (At higher speeds) by 2MPH on the cars we have owned. The same is happening here with the fuel light, there is no need to put on a fuel lamp with almost 3gal left in the tank, that is just being overly cautious.

Now, all that said, you can damage the fuel pump if you run it dry to often, I won't argue that at all, but it has to be run dry, not with just low fuel, and again, 3 gals is not low fuel. Personally it should be about half that amount at about 1.5gal left, maybe even 1, and then it would be a true low fuel light. And then at that point you would know you need to get gas and relatively soon.

Phil

Swacer

These are submersible pumps, aren't they? I believe they are.

If that is the case, they can absolutely be damaged by running the tank low. The minute they are not submerged, they begin to heat up. The amount of fuel required to prevent heat buildup is determined by the layout of the tank internals.

You heat that pump up a number of times, you will burn up the motor.

Now, in regards to running it dry, these pumps should be low head pumps, which means they shouldn't need too much fuel (back pressure) in the tank to operate properly. However, if the flow does get too low (pump can't pull the needed volume to meet demand), and NPSH can't meet NPSHr, the pump will cavitate, over rev and burn up.

I would assume that Toyota has an instrument that monitors pump temperature and speed. if the temp gets too high or the speed is too high, it will trip the pump and your car will stall.

philwojo

Ok so all that being said it if they truly designed it for 3 gal to be left in the tank that is just crap design. They should have used a better pump then or made a new one to work better.

To me it is still just someone doing a CYA on the Lexus side, just like they do with the speedo's and with NAV systems by locking them out. They error on the side of caution, rather than risk any potential law suits.

Swacer

The light coming on with 3 gallons to go is probably more of a protection feature for the driver rather than components. 3 gallons left can range from 50 some to 70 some miles. There are roads where I've driven 30-40 miles without a gas station. They probably want to give you some wiggle room.

I know with my old 1991 Accord, when the fuel light came on, you literally had 10ish miles or less. Heck, one time the light went on, and the car started sputtering, it was legit running on vapors.

Drtbk4ever

As my Dad used to say to me when he would get in the truck after me to find it near empty "It doesn't cost anymore to run on the top half of the tank as opposed to the bottom half".

jim256

I agree with you, but would note that if you have a hybrid and run out you'll typically be waiting for the dealer and a tow to get everything restored. Hybrids protect themselves from exhausting the battery when there is no internal combustion engine to recharge it. Not a fuel pump issue, but a "how low can I go?" issue. It seems a good number of 300h owners frequent both forums, which is good.

philwojo

Yep, totally know that, have had a Prius for almost 10 years, but I don't let it go that far. So driving the 300h is no different, and we traded in an Hybrid Camry.

I am not saying to drive it until empty and then try and squeeze out more from the batteries, but to me the light coming on at 3 gallons left is just silly and is the lawyers getting involved in something they shouldn't.

Does it hurt to fill up before the light, heck no, not at all, and in the winter months I never let it bet below 1/4 tank, if that, just to prevent water buildup. Though with the ethanol they put in gas now that really isn't as big of a deal as it was 20 years ago.

Phil

NX200tLexu

Hi all. I am a new 2016 NX200t owner from last 2 months. I am loving NX except one item which was discussed above, when the low fuel light comes on, it takes about 12 gallons of gas and full tank shows me range of 300 miles. I know people on this forum experienced this problem earlier. What have you done to resolve this? The specs says 15.9 gallon tank so it seems there is about 4 gallons of gas inside when the low indicator light comes on. I asked dealer/ service and they have no clue. They think there is faulty indicator may be. Please share your experience. Thanks!

15RC350F

Mine does the same thing. I just take the light to mean "You're getting low on gas. Find some pretty soon so you don't suck up any of the crap that might be at the bottom of the tank. But if you're 50 miles away from the nearest station, you'll get there just fine."

NX200tLexu

Thanks 15LexNX2t for your response. So does this mean ALL NX200t doing the same thing or we are just few experiencing this? I just have hard time believing that I need to fill-up gas every 250 miles.