Hello,

Recently did a roadtrip from LA to the bay area. I went from having 479 miles left to 19 miles left with the indicator light on. [trip around 360 miles] I go on to refill the tank and noticed that it filled up to full at 10.03 gallons. I am wondering what is the tank size because I thought the tank size is around 14.5 gallons. Is this the same issues that we saw with the Rav4 tank issue?

Thank you!

 

According to the manual for my 350h, the gas tank holds 14.5 gallons, and the low fuel light is supposed to turn on with 2.3 gallons left. I assume it is the same for the 450h+. I have not had to fill up yet.

 

Yeah, it appears it may be one of those issues that rav4 prime has. I was like wow the MPG is realy bad on freeway only to realize that it indeed was getting 36mpg.

 

Seems like this is an issue with the Rav4 Prime currently. What are the other NX450h+ owners seeing?

 

Efficiency is a bit complicated since there are two power sources, gas and battery, that are utilized in potentially inconsistent proportions, so brief background to my response below... My 450h+ was delivered by dealer with an "empty" battery and a "full" tank of gas. I decided I'd break in the engine on hybrid-only for the first ~1k miles (no plug-in or forced engine charging).

Tank capacity: After the first tank, my gas gauge showed completely empty/no bars left. I filled up 11.5gal. Still lots of reserve if 14.5gal is true capacity. Haven't decided yet for this car, but I'd probably figure out how to use at least another gallon before filing up (so if worst-case MPG is 30, then I'd drive up to another 30mi past the end of the gauge). I do miss the analog gauge in my old RX, which would continue showing a reliable measurement past E.

MPG/range: Car display said I had well over 500mi of HV range when I left the dealer, and zero EV range. My driving is mostly freeway (under 80mph), with some local and hills as well, and only occasionally heavy-footed when passing on the freeway. I ended up getting 350mi on the first tank and needed 11.5gal to fill up, so about 30.4mpg. After the first fill-up, car said I had about 515mi range if I remember correctly--I didn't trust it for a second lol. Ended up getting 364mi before the next fill-up, and I still had one bar showing on the fuel gauge; filled up 11.2gal so about 32.5mpg. After 2nd fillup car said I had about 500mi HV range, so it seems to be learning, but still way off from reality. As with all my prior cars from different manufacturers, I don't rely on the car's stated range and instead rely on my own history. Thankfully, the car's lifetime MPG calculation is pretty close to my calculation though, so I think I can rely on that for planning. Once I switch to using EV charging in addition to gas, it'll be a little more complicated to anticipate how far I can go between fill-ups.

 

Same issue here. Seems like the rav4 issue. Drove my 450+ down to no bars with a 14 mile range left and when I filled up it was only 10.5 gallons. Seems the the electronic gauge is way off with capacity - which led to a class action with the rav4 prime.

 

The Last post was back on March. Did Lexus had a fix for this tank capacity issue?

We received the car back in early May. This car was never driven with less than 3/4 tank of gas and mostly driven in EV mode during last few months with around 1.4K miles before our road trip.

Earlier this month, we had a road trip from Orange County, CA to San Jose, similar to OP’s trip, with full tank of gas and fully charged battery. However, we arrived San Jose with no EV (around 2 bars left) and 10 miles left in gas tank on screen with lights on. When I tried to fill up the tank, it only took less than 11 gallons and I almost spill the gas out because I thought I should have been able to pump another 2-3 gallons.

On our way back home, no EV mode at all because we did not charge the battery, but I could pump a little bit more than 11 gallons this time, when there are 22 miles left in tank. Something is wrong with the gas tank capacity. When I calculated the gas mileage, it was less than 30 driving in Normal mode. We drove around 80mph most of time on our way back, but the gas mileage should not be this bad.

Anyway, the EV range is wildly overestimates, too. We are not heavy-foot drivers. The usual EV range is around 30-35 after each full charge. Lexus should explain what is going on here.

 

I have a 2022 NX350h, Usually I refilled the tank to full when there's about 40 miles left, and every time I can only pump 10.2 gallons. And it shows the the distance to empty is ~440 miles. I calculated the MPG, it's 39 which is in the right range.
Who else has the same issue on the same mode?
By the way, my car is manufactured in Japan.

 

You have a reserve of 2.6 gallons when the low fuel light comes on.Lexus is very,very conservative
; see page 190 of your owners manual.

There is no issue. Take a gas can with you sometime if you have any doubts. Once you distance to empty miles goes to zero(0) you can still drive about 100 miles ( 2.6 gallons @ 39 mpg =101.4 miles)

YMMV,
MidCow3

 

I have an NX350h (not 450) and am experiencing the same issues. I always reset my trip meter after each fill up & calculate my mpg. On 3 tanks, I've had the empty light come on at about 500, and I fill up with 11.5 gal (43mpg). I had one time the light came on at 590mi & I put in 11.5 gal (51 mpg, don't believe it). 2 other times I filled up before the empty light cam on and put in 12.6 (still had 2 bars on gauge) and 13.1gal. Don't understand how the empty light is so inconsistent, as well as the on-board mpg calculator. With my 16' RX 350, I would always put in 16 gal after the light came on and my calculated mpg was always 0.1-0.2 with the car's reading.

 

First Tank on my NX350H 37.3 MPG calculated. DTE said 57 miles, actual DTE should have been 148 if you use the 14.5 Gallon tank capacity. Next Tank will compare cars MPG figure vs calculated or actual.

 

I refilled the tank yesterday after the empty light on and 7 miles DTE showed on the screen. I pumped 11.3 Gal for 389 miles calculated by odometer, that's 34.4 MPG. the low MPG maybe due to the cold weather. I feel the insulation of my 2015 RX450h is much better than the NX350h.

 

Lexus is very conservative and has a spare 2.6 gallons when the empty light typically comes on. That seems about right int your case 11.3 + 2.6 = 13.9 still 0.6 gallons off. The DTE is not an accurate measurement at all is is just an estimate Lexus provide and is EXTREMELY CONSERVATIVE,

Take a 5 gallon gas can with you sometime and continue driving until you run out of gas then you will be close to the 14.5 gallons. Then you will know for sure !

YMMV,
Midcow3

 

My question is if the fuel gauge is not working properly or is not calibrated correctly to the amount of fuel that is in the tank . How is the cars Computer going to ever calculate the proper fuel usage. A tank is a tank no matter what size and full is full and empty is empty , but if the Devices that they use has all kinds of set points and dead bands and rate of change calculators that aren’t working I can see why the NX 350 and the Rev 4 is getting bad wraps for poor gas mileage .
I don’t think this is a size problem , it sounds like a miscalculation or a misunderstanding of how they want to use the measured amount of fuel that’s in the tank .

 

I agree with a lot of what you're saying, but the problem (or at least my problem) is that if I wait to fill up until after the warning light comes on, I'm only able to put 11.5 gal in before the pump turns off (I could probably fit another 1-1.5 gal). If I fill up before the light comes on, I put in 12.5 to 13 gal, because I shorted myself on the previous tank. This is exactly what I've read happening with some Rav4 hybrids. I'm worried that the warning light system relies on the computer metrics you talked about, someday I'm going to be running on fumes, thinking I've got another 100mi in range.