2015 ES 350 - Fuel Economy (Low?)

[Neofate]

Hey guys,

I searched but found nothing to answer my question about my 2015 ES 350 I just bought.

I bought this a few weeks ago,.. 2015 Lexus ES 350 with 17k Miles --

I've been monitoring the in car fuel economy computer and trying different things.

I average about 17-18mpg.  It's driven 'light' -- As I'm obviously trying to maximize the mpg right now as it seems low esp. with regulations and so on.

I don't expect 35mpg or anything,.. but I have a 2008 350Z which I've added 100hp to and I get better fuel economy with that sportscar than this Sedan?  I don't get it to be perfectly honest. 

Is this just the way it is?  Normal?  Or what do you guys get from your 2015 (or that same engine anyhow) fuel economy on ES 350's?

I've kept it in ECO,.. tried all the modes and honestly the fuel economy doesn't seem to really change any despite mode -- which I found odd.

 

Even when I drive it ridiculously.. like popping in neutral (it's an auto of course) down long hills.. being mindful of accelerator from red light, up hills, coasting as much as possible and so on -- it doesn't pop up to 25 or 30mpg  on the meter or over X dozen, or hundred miles. 

 

The average over last 3 weeks of about 500-600 miles has been 17-18mpg of granny driving in ECO mode.

 

So if this seems definitely abnormally low for ECO Mode:

What is normal range for City, but driving very non aggressively, driving on average?

As it has a bumper to bumper of course.. if something is off, I'd like to figure it out to some degree before bringing it in and just complaining about fuel economy :)

My last Lexus was an RX 330 -- and it got horrid fuel economy.. 12-14 mpg it seemed.. I just attributed that to weight of SUV and being in full time 4WD etc..  This is different and has the Normal, Sports, and ECO(nomy) modes -- so I'd expect something more around 24-25mpg average with 'granny' driving around the suburbs if you will.

If 17-18 ish mpg is normal.. then so be it. 

Thanks!

[Tom52]

Yes, 17-18 seems very low.  I have a 2015 ES as well and I'm getting around 23 -24 combined.  I use the "ECO" meter as a guide and try to keep the bar as far to the left as possible.  That does mean that I am accelerating slowly, which tends to irritate some of the lead foots but I'm getting the mileage I want and catch up to them at the next light.

[Neofate]

3 hours ago, Tom52 said:

Yes, 17-18 seems very low.  I have a 2015 ES as well and I'm getting around 23 -24 combined.  I use the "ECO" meter as a guide and try to keep the bar as far to the left as possible.  That does mean that I am accelerating slowly, which tends to irritate some of the lead foots but I'm getting the mileage I want and catch up to them at the next light.

Thanks for responding, been waiting on this.

 

It's still getting that 17-18 mpg -- Any ideas on what to do to improve it? Driving like a granny, very slow acceleration,.. etc.  Only time it picks up MPG is when on highway at like 70+ mph really.

Lexus told me to put 87 octane in -- Would that cause the MPG problem? Does it need 91? higher?

It's bumper to bumper warranty -- So, any things that need to be checked/changed whatever if I can prove/find them can be done for free by Lexus - but this sub 20mpg average just doesn't feel right for this car on constant ECO being driven as delicate as humanely possible.  I'm even popping in neutral down hills while watching gauge sometimes.  Which shouldn't be necessary of course.

I figured some others may have some ideas, tips -- Anyone have anything to contribute?  

Thanks,

[LDB]

What tire pressure do you run? You've pulled the air filter to check for obstructions? No prolonged idling anywhere? At not above posted speed limits? Length of normal drive after starting from cold? Number of engine starts in a typical day? Length of time between those starts? I'm sure there are other factors but those are all that come to mind at the moment.

[69HEMI-R/T]

My 2008 ES350 and now my 16 ES350 both got around 22-23 in town and + or - 30mpg on the road at 75mph!  Your ES definitely needs to be checked.  Possibly he computer needs to be re-flashed.  disconnect the negative cable for a few minutes then reconnect and the computer will have to reset parameters. Warning ..... You might lose radio and seat presets when you do his. Not sure.t

[nOraKat]

Hi, I have the 2016 Lexus ES 350 for 8 months and had the same problem. What I noticed is that as I broke in the car/engine, the mileage improved. I drive professionally for a car service like 8 hours a day, 5 days a week.

It started out at 17 mpg combined, but I also idle a lot so that probably brings it down. Now I am at 19.5 - 21 mpg with the same amount of idling. If I did not idle (and ran at a higher tire pressure), I would probably be at a much better mileage.

After my first oil change at 6k, I noticed a difference. I did not wait till 10k like they suggested. I do not recommend waiting till 10k since even at 6k, the oil was very dark and smelled.

Another significant factor is tire pressure: I run mine at 30-32 psi since I have 18" wheels and it feels a bit harsher/stiffer, but I notice 2 more pounds gives a much better mileage than I stated.

Also if you've driven in dusty conditions, check your air filter.  

Also there seems to be a common problem where transmission oil level is improperly filed out the factory. Not sure if this could have an effect..

(BTW looking to trade my 18" wheels for 17"'s.)

[LexusSam]

Didn't know if you guys ever found an answer to your mileage issues.  I just purchased a used 2015 ES 350 with 32K miles on it.  I have run 87 to 93 octane in it.  I get no less than 29.4 mpg (around town).  Getting ready to take a 2400 mile trip and expect to get at least in the mid 30s.  I guess nOraKat could be right... the more they are broken in the better the mileage.  However, this 12-17mpg sounds like there's something not quite right.  My previous 09 ES got great mileage as well.  Usually folks who live in the south get better mileage as in the New England area it's all up and down hills.

[gcrobb]

I've gotten better mileage than that on my 2016 with the cruise set on 90 (85mph speed limit in TX) and typically run at 23-25 combined around town / local toll ways. Would definitely look into having diagnostics run on it since it is currently under warranty.