03 Es300 - Terrible Fuel Economy

[Sherman8r44]

Hi everyone, new here. I just inherited my parents' 03 ES300 with 58K on the odo, and I've noticed that the MPG readout has been hovering around 15. My driving style is a bit "spirited", but not that spirited. The oil has been changed every 3 months, all schedule maintenance has been done on time, and I've tried both regular and premium--there seems to be no difference. Considering my Dad's Jeep Grand Cherokee (4000lbs and V8) gets 14.5, and that IIRC the Lexus' EPA ratings are 20/29, I'm disgusted by the fuel mileage. Has anyone else had this problem? What kind of fuel mileage do you all get? Are there any problem spots I should know about? Thanks!

[SW03ES]

Welcome to the club!

Are you just relying on the computer readout under the speedometer? Try resetting it, that readout isn't very exact. If you calculate the fuel economy by hand you'll find it closer to 18 or 19 probably. I get about 19 city, 25 highway.

[bloxxlex]

Yeah, I get about 18. Oddly enough on my 93 bmw (smaller car, smaller engine) I get about 16. I would think that there would be a bigger difference. On my 94 explorer I get approx 14 mpg. Very disappointing. I wonder if the o2 sensor could be going out?

[Sherman8r44]

Welcome to the club!

Are you just relying on the computer readout under the speedometer? Try resetting it, that readout isn't very exact. If you calculate the fuel economy by hand you'll find it closer to 18 or 19 probably. I get about 19 city, 25 highway.

Thanks!

Yup, I'm going just by the readout. Why is it so inexact? Awhile back (when my parents drove it) I calculated fuel economy to measure premium vs. regular...and both came out to 17 even...even though the readout read around 16. I would be happy with 18 or 19 (I do all suburban driving, so I guess that's "city"), but 15 is HORRIBLE considering i'm pretty sure the ratings are 21/29.

How do I reset the readout?

Bloxxlex--your Explorer isn't that bad considering it's rated at 15/20 by EPA...if you do a lot of highway driving and you're still getting 14 then maybe there's a problem. Wierd about the Bimmer though...

[98es]

My mom's 02 ES averages around 14-15 mpg per the computer. Ever since the transmission was 're-flashed' the mpg has been horrible. Although her driving is about 100% city, i still think that's pretty low for this car. My V8 4runner does better in the city than hers! Although, on the freeway, the ES gets about 25mpg.

[amf1932]

My mom's 02 ES averages around 14-15 mpg per the computer. Ever since the transmission was 're-flashed' the mpg has been horrible. Although her driving is about 100% city, i still think that's pretty low for this car. My V8 4runner does better in the city than hers! Although, on the freeway, the ES gets about 25mpg.

I always figured that the gas mileage had to suffer for city driving after the ECU was flashed, mainly because the transmission is held to a higher RPM before it shifted to a higher gear. I know this happened with my '03 ES, even though some members that had the flash claim that their mileage was no worse. I also read that this flash made the specifications for ULEV no more applicable for this car!!

[Sherman8r44]

How do I reset the readout?

Anyone?

[98es]

Press mode until you get to the mpg, then hold down reset.

[steviej]

How do I reset the readout?

Anyone?

using the reset button on the steering wheel only clears the immediate memory for the mpg calculations.

If you disconnect the negative cable to your battery for about 10 second, the mpg computer goes back to the default of about 345 "mile before empty" when the tank is filled. However, this will also reset your ECU to the default as well as clear your radio and memory seat presets. The tranny will begin the process of relearning your habits all over again.

steviej