amason61

Okay, here's my story. I purchased a one-owner, 2006 ES330 with 17800k original miles on 4/14/15. The car is immaculate. It has been inspected by the local Lexus dealer and passed with no issues. The car drives smoothly with no surges, etc. I have Brand New Cooper Ultra Touring S5 tires on the car. They are properly inflated (nitrogen). My issue is poor gas mileage. In the 2 months I have owned the vehicle this is my mileage record (taking actual miles driven per tank ÷ gallons to fill the tank). by the way, I disconnected the battery for 30 minutes prior to my first road trip to reset the ECU and still managed to only get as "high" as 23 mpg.

Apr. 14 - Mix of mostly highway and some city - 19.2 mpg, topped tank at 13.82 (DTE said less than 10 miles to go), 87 Octane

Apr. 18 - Mostly city - 17.3 mpg, topped off at 14.47, 87 Octane

Apr. 27 - ALL highway - 19.7 mpg (cruise set on 80mph),, topped the tank at 14.55, 93 Octane

Apr. 29 - All highway - 21.7 mpg (cruise set on 80mph),, topped the tank at 15.26, 93 Octane

Apr 29 - Mostly highway - 23.2 mpg (cruise set on 80mph), topped off at 11.69, 93 Octane

May 1 - All highway - 21.1 mpg, topped off at 10.80, 87 Octane

May 1 - All highway, 21.0 mpg, topped off at 15.28, 87 Octane

May 1 - Mostly highway, 18.6, topped off at 15.18, 87 Octane

May 8 - Mostly city, 16.3, topped off at 15.05, 87 Octane

May 19 - all city - 16.7, topped off at 15.07, 87 Octane

May 30 - all city - 16.7, topped off at 14.76, 87 Octane

A couple of questions: 1) My DTE indicator runs to near zero, but the most I have ever put in the tank was 15.26 gallons. Is that normal? That means I had 3 more gallons of fuel, correct? And, 2) does my mileage suck as bad as I think it does? I know this is not a 4-cylinder, but running 93 Octane on the highway and only getting a maximum of 23 mpg? What am I missing?

KLF

Your mileage should be better than that. I've never put anything but 87 octane in my '05, and I typically get 22-24 mpg, and very little of that is highway.

Disconnecting the battery doesn't necessarily reset the ECU. They have non-volatile flash memory in them for some things, you really need a code reader to do a full reset. Most parts stores will do it for free, but I'm not sure they all really know what they're doing as they usually are pulling codes just to sell you parts.

Megafast13

Going 80mph, that is what I'd consider good in this car. I normally do 65-70mph cruise control and get about 25. They weren't as concerned about MPG when making these cars back in the day. Consider having your MAF sensor cleaned it may help a bit. Since you reset your system, the rpm's may not be where your driving style is quite yet and they are often higher RPM's than they need to be for a while.

speedkar9

I get 12.5L/100 km city (18MPG) and 10.0L/100km (23 MPG) highway with my 2005 ES330, with 87 Octane fuel.

Consider changing the spark plugs, cleaning the throttle body, PCV valve, running some fuel injector cleaner and maybe even switching to synthetic oil. The rest is mostly determined by your driving style.

Oro

I find that ethanol kills my mileage quite a lot,so factor that in. I believe the epa est. for these are 29 highway, figured at running 55/60 and with 91 octane gas, no ethanol.

Example, running 87 or 89 octane ethanol blend, our 2002 (should be the same as yours from the EPA estimates) will get 24 mpg (mostly) highway 65/70mph, commuting/unladen. This spring we took a pure highway trip and as an experiment, I used an app to locate some 93 octane "real" gas (non ethanol/E0), and got 29+mpg with 2 adults, 2 kids, luggage, cooler, etc, steady 70, and some mileage running 80. I was pretty impressed. I have been all through this car in the last year and every sensor, etc. is clean/functioning, plugs show a correct burn on reading them, and it runs full synthetic oil and tranny fluid. I also once or 2x a year run some SeaFoam through the brake booster vacuum line into the intake to clean things up.

Sound like your mileage is still down and checking what Speedkar9 said will help. I have found the MAF sensor can make a big difference clean vs. dirty.

the DTE indicators and computer mpg estimates never work correctly so pay no attention to those.

Brandon593

I have the same car and have always wondered, "am I really only getting 19mpg in the city and 21 combined?" Quick fix - premium gas. The car runs better and I get a few mpg's higher than regular. my highway mileage is 28mpg averaging 70-80mph. Huge improvement. Hope this helps. Also, little things like replacing a dirty air intake filter and keeping your tires properly inflated helps with that, too. Everyone drives differently in the "city", so you won't really get a definite answer as to what mpg you should be getting. I average 20mpg in the city, but I do have a bit of a heavy foot.

Brandon593

I forgot one thing that may help you. Go to your Lexus dealer and ask them to flash the ECU in the car. They'll know what you mean. These cars have adaptive transmissions and will learn your driving habits. This doesn't only make your driving experience more enjoyable, but it can help your gas mileage since the car will know whose foot is on the pedal. Just so you know, the car will drive pretty different for up to a week after the ECU is flashed. Don't worry - it's just the car learning your habits. Cool, right?

amason61

Thanks, everyone, for the feedback. I checked the MAF sensor. Looked pretty clean to me, but I went ahead and cleaned it anyway. Air filter is in like-new condition. I ran a bottle of fuel injector cleaner through the last tankful. I will try the Premium Gas for awhile and see if that shows any additional improvement. I don't have another long road trip planned until August, though.

I will talk to my Lexus dealer about flashing the ECU the next time I am there.

Appreciate all the suggestions and feedback. Will keep everyone posted.

speedkar9

While I do manual fuel consumption calculations every time I fill up, I have found my ES330's average fuel consumption meter to be very accurate.

The annoying accelerator lag and lazy transmission shifts in the ES330 causes me to punch the gas more to get response, making me heavy footed in the city. In my Solara with a drive by cable throttle, the car is much more lively and is arguably faster accelerating in traffic, making me light footed.

Reflashing the ECU means reprogramming it with a different software. What you meant is to reset the ECU to clear its driving style memory. This can be done yourself by disconnecting the negative battery terminal for 5-10 mins.

PuReChaos

Correct. I currently work at the dealership and we've never reflashed an ECU just to reset driving style memory. They could potentially charge you up to an hour of labor for removing the negative battery terminal.

285exp

Question 1, yes, that's perfectly normal. I was driving my wife's 04 ES330 this weekend, and with 9 miles to go on the DTE display it took 15 gallons. They will always make them very conservative because they know you'd be a lot more irritated, plus it can be potentially dangerous, if it ran dry when it still said you had more miles to go than if you have to fill up a little early. Plus, it's dumb to cut it close if you don't have to.

Your city mileage looks pretty normal, 23 highway is a bit low, even running at 80. Our 330 gets around 25-26 running at 76 mph on 87 octane. If you have the patience, try running a bit slower, early to mid 70's, and see how that affects the mileage. If it gets 25 or so, then there's probably not much wrong with it, and dropping some money on cleaning MAF sensor, adding fuel system cleaners, and using synthetic lubes isn't going to do much to improve it.

As you noticed, running 93 didn't gain you much, and that's been my experience, maybe 3-4% at most. Around here premium costs 10% more than regular, so while you might get a bit better mileage your cost per mile will be more.

Running E0 instead of E10 can increase your mileage around 3%, so if you pay only 3% or less additionally for it, then makes economic sense, otherwise it's cheaper to run E10.

If you get nitrogen free, then fine, if you pay for it it's pretty much a scam. The advantage for race cars and airplanes is real, for passenger cars not so much. You're better off keeping an eye on the pressure regularly and adjusting as necessary. Too many people think that nitrogen makes it so you don't have to, and that ain't so.

BDSL

Vehicle: 06 ES330
Location: Ontario, Canada
Fuel: 87 Octane

Highway @ 70mph with no AC: 28mpg
Highway @ 70mph with AC: 27mpg
City: Horrible......around 18mpg

speedkar9

How many km on your ES? How do you get 27 MPG hwy around here? What area are you in? Do you use Shell 87 gas?

Oro

That sounds like parroting the EPA propaganda, which is based purely on nominal thermal content of the blend, and not actual empirical results. Real-world results in working engines don't conform neatly to what the government, environmental, and corn state lobbyists try to make you believe.

BDSL

It has 150k km.
I get 27-28mpg during weekends traveling between Milton/Mississauga/Markham on 401/407/404.
I use PetroCanada 87oct on the last few tanks.....because of the 3cents off promotion right now.