Swobro

Thanks and I'll keep an eye on that. My last daily driver was a '01 Maxima and I had SIGNIFICANT issues with the O2 sensors while running on premium unleaded (although I really don't know what the cause of failure was and I found out that quite a few other Maxima owners had the same issue. I must have replaced 3 or 4 sensors at $300+ per.

By the way, do the ES models have frequent (check engine light) O2 sensor issues?

dreyfus

Well I finally took an extended highway trip so I have real highway mileage results.

After 1,700 or so miles my around-town mileage is consistently 26 mpg (using premium).

After driving on I-95 five hours each way (72 mph on cruise w/AC) my mileage was 33 mpg.

These figures are from filling up and dividing the number of miles since the last fill-up by the number of gallons burned. My trip and tank average meters are usually both within 1 mpg of my figures.

For this car I am very, very pleased with this amount of economy.

Kaius88

Im consistently getting 19 - 20 mpg from city driving to and from work. Basically 20 miles each way all local..... Some canyon hill driving, and a small stretch of hwy at most. I am not aggressive driver....i think the mpg goes down while i stop at the light....so many lights. I cant wait to take a road trip with this car...it needs to RUN FREELY for a change.

Macklin

I'm seeing similar numbers so far. My gas mileage did seem to go up a click or two after the first 1500 miles, which is even better. I filled up the other day and immediately got on the interstate to work. The average tank mileage read 36.5 when I got to the bottom of the off ramp.

Probably an aberation, but hey....can't wait to take an extended trip to find out.

gappell

I just returned from a 3000 mile trip from Florida to Vermont and back. My ES350 has every option and the air conditioner was on during the trip as temperatures approached 100 degrees. I had lots of luggage and my wife along to keep me company. I averaged between 70 and 80 MPH speeds on the Interstates. The car averaged 30.4 MPG on the trip computer. I also computed the MPG on each tank and had very close agreement. I used mostly premium fuel. I did use mid-range 89 octane on 2 tank fills and did not notice any difference.

In regards to using lower octane fuel, the compression ratio of the ES350 requires premium for optimum efficiency. Using lower octane fuel causes faster burning requiring changes in spark advance. The Lexus computer does a fine job of correcting the spark advance. However, the question remains about loss of efficiency and potential engine damage. Audible engine ping is difficult to hear in the quite Lexus.

Kaius88

wait, the gas mileage gets better as you wear it in??? how does that happen? Anyway, i drove my ES350 at 11pm last night to get some fresh air.... no traffic.... drove a good 50 miles.... The average was 33.6 mpg! what a difference when there is no traffic. And this car's is even more efficient than my old 1.8L engine Miata, which does only 30 mpg on hwy! This is freakin insane... but on normal streets, and stop-n-go traffic, the ES350 is still averaging about 19 mpg whereas the miata was doing 25 mpg.

Bottomline, the ES350 efficiency only comes into play at higher speeds.

tnfan

I am getting between 21 and 22 MPG in city stop and go driving. On the road about 33 MPG. I now have close to 6k miles on the car and am very happy with the fuel economy.

PsychDoc

That's about what I have been getting though my hwy. mpg is a bit lower. About 30 mpg.

Mpg figures like this on a 3600 lb. car with 272 HP and 0-60 times of 6.2" are simply amazing!

And I can't wait until the weather cools off and I can run without A/C. I'll bet mpg numbers will improve by about 7-10%.

twister

This car is like a fine wine - gets better with age

I only have 600 miles on it, but have noticed that gas mileage got slightly better on my stop'n'go daily route. Ironically, with my first fill-up (Octane 93) I was getting 20-21mpg, and after my second fill-up (Octane 89) its about 23-24mpg. Only had two gas fill-ups so far, but will keep a track of it. I also noticed a significantly better acceleration after the first couple hundred miles. When I first got the car, I felt a little hesitation when you step on the gas right away, but now it smooth like a butter. A few time already while not looking at speedometer, I was wondering how come I just pushed the gas and didn't feel acceleration. Than, in that split second I look to see I'm at 45mph already. Just came back from the lunch with a few of my buddies from work, they both commented they didn't feel the acceleration at all, just saw trees passing by much faster I felt like a proud daddy, the same way how I feel when I get compliments from daycare where my daughter goes

dshahs420

You get better gas mileage as the car gets broken in(think of a baseball glove). In a new car there is more wear and more friction, and as the car gets older there is less friction, you can see this evidence by getting a Used Oil Analysis done and usually the first 10-15,000 miles you see higher wear numbers in iron, tin, lead, copper and aluminum(all from the pistons and engine block) plus higher numbers in silicon from the piston seals. As the car gets older the engine gets broken in and less friction thus better fuel mileage. Try running a 0w20 oil in the car and the higher gas mileage will be evident albeit being less than 0.5%

P.S. Getting in a habit of keeping your fuel injectors clean also goes a long way. I usually put SI1 from redline into my tank at every oil change. The trick is to only fill 1/2 your gas tank and adding the fuel cleaner thus getting a higher concentration of the fuel cleaner. Try it out and keep your injectors clean. http://www.redlineoil.com/products_fueladditives.asp you can also try FP60, its also a good product.

Kaius88

Thats good tip and great info. Thanks dshahs!

Har

So for best results using the Redline Product, on an empty gas tank add add the total contents of the Redline Sl1 to the tank, then add premium gas to half tank then re-fuel to full tank after hitting empty again? Do this procedure evry 5K miles or so to keep your injectors clean?

Does Lexus do injector cleaning under the normal maitenance schedule? My 2005 RX 330 is due for the 30K, should I do this Redline therepy before bringing it in for service?

amf1932

Gasoline manufacturers put additives in their fuel to keep your injectors clean. I have NEVER had any problems in this area in any of my 4 Lexus cars that I owned, so I don't intend using any, unless I have a problem, besides Lexus as well as other auto manufacturers also advises to NOT use any additives.

Har

Alan,
What band gasoline and octane do you typically use?
I have been using Sam's Club and BJ's alternating between regualr and preimium mostly for convenience and to save a few pennies.
Harold

dshahs420

Yes, pour in the whole bottle of content into your gas tank when its half full or when you fill up just fill to 1/2 a tank and run the fuel until the low fuel idiot light comes on. Do this every 5000 miles and your injectors will stay clean and also increase the life of your fuel pump. Also try to fill up when your fuel gauge shows 1/4 tank of fuel remaining, it keep debris deposits on the bottom of the tank. Running your gas tank to near empty can clog up the fuel system real fast. Its true that fuel nowadays has lots of detergents and is cleaner but over the years as the miles rack on, even the minute amounts of debris add up and clog the injectors. Just like cholesterol clog up your arteries over time and can decrease blood flow, thus oxygen to the vital parts of your organs, fuel works the same way in cars and injectors. If you are planning on keeping the car for more than 100,000 miles its good preventative maintenance. If you keep your car for less than 100,000, heck dont spend extra money of the fuel injector cleaners.

Har, just go to advance auto parts and buy a bottle of redline SI1 or FP(fuel power)60 and add it yourself, doesnt matter before or after the service. Dont have Lexus do it, cuz they probably use something cheap like STP and charge you more than the better products like FP60 or redline. Rule of thumb, make a habit of dumping a bottle of this every oil change and your injectors will stay clean. Go to www.bobistheoilguy.com and read up on fuel additives. I have learnt a lot from that website.