4TehNguyen

iTrader: (1)

I make 21.5 mpg 100% city on my IS350 EPA lists the IS350 as having 18 mpg city, and it doesnt weigh a whole lot less than a GS. Turn your gauge cluster display to Current MPG, using that you will learn how to control the throttle properly to achieve max mpg. You can even turn it into some kind of game to get the bar as far to the right as you can during normal driving, thats what I did. This will help a lot but it cant fight things like stop and go traffic, only finding a new route can do that.

Keep your tires inflated properly, minimize braking and sudden stops, coast when you know you are going to be stopping soon at a red light, etc

I8ABMR

just went from LA to Phoenix on 3/4 tank. Unbelievable! The computer was reading 28 mpg. In the city I get 22. mixed city and highway I get 24-25 mpg

sf7307

Just wanted to let everyone know we got nearly 29 miles to the gallon (GS350RWD) on a trip to LA this weekend (or at least after gassing up south of Gilroy)

TwiBlueG35

Since IS350 and GS350 use the same engine, I think their fuel economy should be comparable. My IS350 has about four thousand miles on it and averaging about 19.8 mpg.

Net Junky

iTrader: (4)

i've driven to work on the freeway going 40 miles about 65-80 mph and got 32mpg. My average is 26-28 mpg with mix city and highway. Guess I'm glad I have a GS300...

flipside909

I got pretty phenomenal mileage with an 08 GS460 this past weekend. 27mpg hwy driving. I'll be writing up my results shortly.

Vesuvius

I am on my third or 4th tank and getting around 14mpg or less, granted it is all mostly city mileage. I am going to wait till I hit the freeway for a trip and a few more tanks, if it is substantially less then what the sicker says I definitely regret my decision since I do allot of driving. I am using the after refill mpg and the average mpg on the wheel and drive in eco only and drive like an old man. My brother has the 6 speed from a year ago and gets 18 all around, still that is much less then sticker. Anyone think of class action suit etc?? They have to be accurate as many buy these cars expecting what sticker says.

Mistahoo

I was getting 14-18 city and 18-20 freeway. I got a bad batch of chevron gas and to top it off my air filter and throttle body was dirty. Replaced the filter, cleaned the throttle body, and put in some fuel injector cleaner and I'm back at about 18-20 city, 22-25 freeway with slight, and 25-30 freeway with no traffic

Philsogood

Maybe I need to do the same because I'm only getting 14 mpg. How do I clean the throttle body ? I'm installing k&n filters tomorrow

Steve2424

There's a write up on it in the 3rd gen section. One member broker it down with pictures even, and I'm sure youtube has a good walkthrough.

Just be mindful that the flap that controls the opening and closing of the throttle body is delicate (opens electronically I think -- not too sure on this) so gently clean it without applying too much pressure. Good luck and let us know if you notice any improvements!

Broncosi

Tl;dr: Unbolt your intake from the intake manifold, have someone push down the gas pedal (**with the car off**), spray cleaner in. If you try to open the throttle plate manually, you could have to reprogram your computer.

blue00

make sure that a brake caliper did not get stuck. after driving check if any wheels are hot, if so brake may be eating up your gas mileage

Broncosi

how would a caliper get stuck and you not notice immediately? Do your brake pads normally get stuck to your rotors on your gs? That's like the opposite of the toyota recall with gas pedals.