nickboy96

I have a 2010 Lexus is250 and for some reason i get an average of 17.6 mpg, and i usually don't push the car. Any one else ever have this problem.When i fill up, my full tank of gas gives my only 270 miles, while my friend with the same car gets 310. plz help

mmartin061

Many factors have to be taken into consideration when factoring fuel mileage. I have an 08 Rav4 4cylinder that gets usually 21-23 hwy. Every tank could be different driving the same exact route everyday. It also has a 4 speed auto so no OD. Fuel sucker 4, and the 4cylinder needs to be a 6, the engine works harder to achieve speed more fuel being consumed. Temperature plays a big part as well as if you are driving into a head wind. I only got 15.8mpg driving into a strong headwind in the dead of winter. That is exactly 11-12 mpg less than on non reformed gas driving in milder conditions and no headwind. Many many factors play a huge part. 55-60 is your sweet spot for mpg on freeway getting over that causes your car to work that much harder against the air it's pushing through. Dont worry 17.6 isnt bad for city driving

Icy350

iTrader: (18)

I drive nyc and I get 14-17 LOL we are in the same boat

is250fsprt

I'm averaging 21.2 mpg combined almost all the the time on my is350.

DryEye

I was having the same problem with my IS350. when I use to fill up my gas tank, the avg. range after the fill up would be around 335-345. Then all of sudden it started drop to 325, then 310, then 290, then 280. My driving style hasn't changed, I keep up with maintenance, tire pressure are to specs, cleaned my throttle body and MAF, changed my air filter, and yet the MPG was still low. So finally I decided to just disconnect the negative terminal on the battery to reset the ecu, and voila, It worked. It brought my avg. range back up to 338 and mpg jumped back up to 25 mpg. So try resetting the ecu. It worked for me so it might work for you.

Eduskator

Winter?

My AWD IS250 2011 average roughly 17-18 MPG right now (13-14 liters / 100KM) and it's -20C outside (-4F). We had -45 (-50F) last W/E... lol

But in summer...average is 19-20. I am not a ''heavy'' driver (car always shifts @ 2K rpm)

Bichon

A little spirited driving has a much smaller effect on gas mileage than short trips do, especially in cold weather.

Vanze

i get around 22 on average in an 09 awd but i push the car and go wot pretty regularly.. i remember on the "why get is250 instead of is350" post when that guy said he got 30 mpg in an is350 going 80-90 mph.. I lol'd

Eduskator

Yes you are right... I live 2 miles from my workplace and traffic is aweful. The car is almost never at operating temp except on weekends... It burns fuel like hell.

Tro209

They're could be a few reasons.

Make sure you check your air filter that's it's not clogged and starving your engine for air (our engine are pretty sensitive to that). Also if your doing short trips vs long trips your tank Avg suffers as a whole since stop and go wastes much more gas than continues stretches of road does. Be sure to check that your PWR mode isn't accidentally on and also don't drive in S mode.

If that's doesn't help then you may possibly have a faulty O2 sensor or something like that. When my brothers failed on his IS250 his Mpg were all over the place. From high amazing Mpg's to crazy low level readings. In other words it was broken. Other than that I guess if you get bad mpg it's just driver related (your fault) lol.

Eduskator

Just fueled up a few minutes ago...

156km driven (city, lot of traffic), 26.940L consumed = 17.26L/100km (13.84 MPG)

Car is a 2011 and has 50k miles on it. Engine tune-up done before winter, everything is A1.

Welcome to Canadian Winters...lol

DVS

gas is cheap now so no worry but seriously check your tire pressures and make sure ECT button is not on

Tro209

I didn't think about tire pressure

Yeah make sure you check that as well. Also, when was the last time you had your oil changed?? That could also be a factor , along with the weather as someone mentioned. Or if you just live in an area with lots of uphills or high altitude and what not

Namster

iTrader: (20)

Funny thing is I drive with ECT on all the time and I still get 25-26mpg (mixed city 30% / highway/70%) on 07 IS250. I WOT from time to time too and every fill up the tank shows ~375miles range.

The IS350 on the other hand is 21mpg with sport mode and tank shows 335miles range.

If your IS250 gets worse mpg than IS350, then something is wrong with the car. I would check routine oil maintenance and tire pressure and other factors as others have mentioned.

nickboy96

i just put and intake in, but i installed it properly, u guys think with out that heat shield its making an impact