pansophy

I just got a new IS 350 AWD F Sport with just 5 miles on it. I am a former Prius driver, so I was prepared for lower gas mileage, but on my first tank of gas (dealer provided) I have averaged 11 MPG in normal mode.

I would say I am about 80% city, 20% Hwy and I have not driven it hard. I have driven about 150 miles and I have about 1/4 tank of gas left. I haven't seen anyone post less than say 16 MPG.

I spoke to the dealer and they want me to try a second tank of gas before they really look at it. Anyone have any ideas on what might be the cause of this, or what I should do about it with the dealer?

gvan1998

gas mileage gets better as the car breaks in. I averaged 16mpg my first tank 350 rwd. Now im averaging 22-24 mpg.

s4awd

I know how you feel. I have a 350 F sport AWD and averaging 17mpg and have a Prius as well. Going back to low mpgs blows. I'm not giving up my prius for anything. Hatchback, size,47mpg average and has nearly all the tech of the lexus. Most of it is the same of course. Def going electric next. Using so much gas seems stupid nowadays. I leave my 350 on econ which defeats the purpose of getting the car but whatevs. ugh

pansophy

I knew I wasn't going to get 20, but I was expecting more like 16-18mpg. 11mpg seems like something is wrong with the car to me. I tried econ and it didn't seem to make a difference and it definitely took fun out of the car.

yardie876

Could be a combination of engine break-in, AWD, and winter blend gas. That's pretty low though.

morton87

I have an 350 AWD and the only time i get that low is if i'am screwing round in some of the hills around me taking the corner hard or stepping on the gas a lot. Otherwise i average about 15-17 in town and 25 -27 on the freeway for long trips as long as the cruising speed is reasonable (80-83 mph)

JDR76

I think you need to run a full tank before drawing any conclusions.

I assume this is the tank the car came with. If that's the case, you don't really know how long the car may have idled on this tank while at the dealer, which will impact your overall mileage. Put in a fresh tank and see how it goes.

4TehNguyen

iTrader: (1)

car probably idles a lot on its first tank of gas, should reset your mpg on the next tank to get a more accurate calculation.

WWM

Low temperatures are going to kill fuel economy too. -10C knocks off probably 15-20% from what you'd normally get. Getting just above 0 improves things drastically and you probably reach normal levels above 10C.

dbs600

Thank you for your posts.

Please review these two threads and note my posts therein:

https://www.clublexus.com/forums/is-...0-f-sport.html

https://www.clublexus.com/forums/is-...s-getting.html

I too am experiencing same, and at nearly 5k miles, my mpg's have not improved.

This is exceptionally frustrating and I'd love resolution already.

Please post in the above threads - to maintain continuity and awareness of the problem.

Enough of the break-in, winter fuel and temperature and idling theories; there's an issue.

Very upset. :|

CharlieVo

something isnt right, if you only get 11mpg.

bforbrian

iTrader: (3)

The more miles you rack up, the more realistic. The #s will improve.

theoryguy3

I'm geting 18mpg , sucks