Does it seem to be running normally? Otherwise, shouldn't be much wrong at 25k miles. Driving habits? Tire pressure?

 

19.7 mpg on freeway driving from Austin to Dallas. Literally laughable.

What can I do to increase MPG other than increasing tire pressure?

 

No idea what year/model/miles you're driving. Yeah, tire pressure will help a little bit. Otherwise, your style of driving maybe?

 

2017 RX 350 @ 80K miles. I was driving 70-80 MPH.

I did notice it a reading of 19mph N wind in the weather section of the info panel. Is that a headwind if I'm traveling north? That could explain why my MPG was so low.

 

That seems really unusual for this car for pure highway driving at constant 75 mph speed.

I average around 25 mpg 9.5 ish l/100km on my 2016 when on highway with average speed of 110-120. Overall average is around 18 mpg 12-13 l/100k.

Keep in mind that SUVs are big bicks for aerodynamics. If you go faster they burn a lot more fuel. They are also heavy, so accelerating faster will also use much more fuel.

 

Miles per gallon for a full tank on a 2021 Lexus RX 350 base , 2FD with 20" wheels and Goodyear Eagle Touring tires filled to recommended pressure 33 psi. Starting at 30000 miles.

1st tank 18.20 Eco mode Samsclub regular gas
2nd tank 21.47 Eco mode Samsclub regular gas ( Highway mostly , spirited driving on highway)
3rd tank 19.75 Eco mode Samsclub regular gas ( City mostly)
4th tank 22.12 Eco mode Samsclub Regular gas ( Highway Mostly , spirited driving on highway)

So i don't know how they claim 20 city and 27 Highway . The real numbers are way below what they state.

 

I have a 2016 F Sport, regularly get 8 L per 100 (29.4 mpg) on the freeway and 12 LP100 (19.6 mpg)
Close to the claim. ECO mode is pointless, just holds gears longer, may make car labor more which means more fuel. Just use Normal Mode. You say "spirited driving", THAT'S probably where you chew more fuel, particularly using ECO Mode. You use regular gas, is regular used for the testing where they get 20/27? I seem to remember I read that they use Premium fuel for the testing to decrease the fuel consumption figure. I'm in Australia, our RX's state to use Premium which I do, RON 95. Your regular is RON 91.

 

Your local mpg seems right on target. Agree that "spirited driving" has a lot to do with the hwy mileage.

 

I recently acquired a 16 rx350 and am getting pretty horrible IMO fuel mileage at 16.5L/100kms

the car has ~136k on it, any ideas for me or is that just how they are in the city?

I do have it in eco mode and noticed it likes to shift weird at times (I’ve read that’s the nature of the 8speed). I also have a 16 f350, it’s a 6speed but has an ‘adaptive transmission’ do Lexus’ use similar tech?

I do notice a bit of a rough idle when it’s cold, I was under the impression this was normal though for a vehicle warming up

I will check the air filter today (up until my ownership it has been serviced at a Lexus dealership)

I have also read online my map sensor could be causing issues, are there clear run ability symptoms that would point to this?

thanks in advance!!

btw otherwise love the vehicle, we also have a 18 450H in the family. Seems that gets ~11l/100km in the city but being hybrid that gain makes sense

 

I have a 2020 and mileage really depends on driving habits. On highway I get about 24 mph but in city with stop and go it drops to about 17 mpg.....sorry, I am in US so we use the goofy units. So your mileage is definitely low....about 14 mpg.

Dirty Air filter and/or MAF sensor, and old spark plugs could all also contribute. With 136k on the engine (km or miles) the plugs may be due.

 

16.5 l/100kms is a bit low for city driving...depends on how bad the stop and go, idle time, temperature, etc.
16.5 is 17 mpg (imp)
I never found eco got better gas milage, just horrible acceleration.

I get a bit better (22 RX350) in the city (14 avg) and substantially better on the highway (9.8 avg) Almost the same as my 6.2l 4x4 pick up truck!

Like Quantum501 says, check Filters, plugs, etc.

 

Am I really getting 40mpg? When Im on the highway and I reset the mpg I get 35-40mpg until I slow down.

Anyone else able to achieve this?

 

Better to ask in the RX forums. What years is yours? I'll move it over

 

Thanks, its a 2019

 

No, we've never seen such a number in our 2019 RX.