graphicguy

I thought you guys would get a charge out of this.

Went to the Mazda dealer to get my oil changed. They ended up putting 10W30 in it because they said the couldn't find any 5W20 (what BS but that's a story for a different topic).

When I mentioned to the service writer that MPG seemed low, he made a note of it for the tech to check out. Here's what the service tech wrote on my service ticket:

"S17-Fuel trims OK....No codes stored in system...all tire pressures OK....customer should keep RPMs under 3,500 for better fuel economy"

Under 3,500 RPMs? Hell, I'd be passed by every granny on the interstate that's driving a Crown Vic if I kept it under 3,500 RPMs.

My service tech is a "maroon".

jem777

"Customer should keep RX-8 parked in driveway for maximum fuel economy."

graphicguy

LOL! Better yet, only drive it in reverse.

msrecant

If nothing shows up in the tech manual fault-tree, then you (and I)obviously don't have a problem.

miata2rx8

I am getting 185- 200 miles per 'tank' (when light comes on, refill and reset odometer). I drive pretty conservatively (most of the time).

Kewl

I have only 1600 miles on the car, but last fill-up I got 19.4 mpg. Mostly in town driving and I don't adhere to any particular rpm driving range. If I feel like, and road conditions allow, the foot is in the gas.

O.R.A.

That really is not that bad. I mean, my '93 Protege gets about 23mpg city. My WRX gets 19mpg city also.

tminus3

Ok I noticed something interesting:

Brand of gas seems to make a difference in gas mileage.

WAWA (Regular) - 20-21 MPG
Mobil (Regular) - 16-18 MPG
Exxon (Regular) - 18-20 MPG

WAWA (Premium) - 19-20 MPG
Mobil (Premium) - 16-18 MPG

I'm not sure what to make of this infomation I have gathered except I go to WAWA and get Regular if I want my tank to last. BTW, I run it to 6k on most shifts and I don't baby it. I also have 1640 miles on the car.

Lets see if we can slowly but surely figure it out.

Artifex

hmm keep RPMs under 3,500 ?!

Sounds like that tech needs to talk to the product manager.

At the Sevenstock banquet the Rx-8 product Manager (who happens to read this forum) said that this was not neccessary. He suggested that we just drive the car not worry about RPMs and the fuel economy will be inline with their tests. It's kind of strange that a tech would suggest this.

I don't want to misquote him, so if somebody has a video clip of him addressing horsepower and gas mileage could you post a link? Or better yet if you are reading could you chime in? I apologize that I forgot your name and it's not listed on the sevenstock site anymore

I posted a while back, but now that my 8 has 2400mi on it I can give an updated comparison of same drive(all hwy 130mi each way), same driving styles
87 Rx-7 turbo : 21mpg
04 rx-8 tour: 15mpg

RenesisPower

This is my first rotary engined car and I knew that rotaries are not the most fuel efficient motors around. My issue is with the range between fill ups. I am getting only 210 miles between fill ups.

Mazda should have put in a larger gas tank in the RX-8 so that one can get about 300 miles between fill ups.

msrecant

I just hit 2000 miles and things have started to change.

First 1800 miles - 13.8 mpg

Last 200 miles - 15 mpg
(1800 to 2000)

Mine is an early build US RX-8 (May 2003).

My mileage is almost all in-town stop-and-go driving. I have tried a variety of driving modes (DCS/TCS on and off) and driving styles (from Grandma to Evil Knevil) with little mpg variation. I consistently use Texaco.

At least I finally made it to the bottom of the scale.

8_wannabe

Congrats for getting this far. Your pattern sounds a lot like mine; early build and improvement after 2K. I average around 17 mpg now. As you say, it seems to have little to do with how I drive. I have tried every strategy suggested on this forum, kept good records, and see no correlation between octane/driving habits/mileage. I am up to 3700 miles now with about 60/40 city/hiway.

shebam

I-95, D.C. to Richmond and back, 21.2 MPG on Shell 93 Octane, about 1500 mi. on car built late May. Local commute mileage has crept up to 14.75. 6SPD GT.

VelocityRedRX8

Mine is similar, with about 450 miles on the Odometer. I didn't buy the car for fuel economy, but this does indeed seem pretty low. Also, I drive mixed - from conservative to pretty heavy footed. Hoping for some improvement with additional miles...

mikeb

225 a tank for me

qumatru

i'm begining to worry guys... my car has got some serious problems concerning gas consumption. i get 25% in the city, 15-18% highway, and 30% sporty driving. That's liters/100km. in miles per gallon that would be about 9.4 in the city and....oh you do the math for the others. I'm really scared and I'm from europe. a liter of gas here costs 1.3 dollars. i've used over 5000$ worth of fuel in just 10.000 km and this sucks. apart from that i love the car... wish it were a lot more powerful, but maybe in the next generations.

willhave8

2 years 4 months has gone by since this thread last had a post. That must be a record.

Anyway... All I will tell you is that your results are abnormally low.

In the winter (now) driving with winter tires, 5 miles each way to work, I see 15 MPG. In the summer that same path gets me 17 MPG on 'summer' tires. 100% highway at 75MPH, nets me 21 to 22 MPG.

Temperatures , tires, driving speed (e.g. highway vs. city) and how much time you spend over 4000RPM effect MPG. If you are within reasonable limits on those things and are still seeing less than 13 to 15MPG, have your car serviced.

zoom44

POOR FUEL ECONOMY

DESCRIPTION


The fuel economy is unsatisfactory.

POSSIBLE CAUSE


*

Contaminated air cleaner element
*

Air suction at intake-air system (between MAF sensor and intake ports)
*

Poor fuel quality
*

Inadequate fuel pressure
*

Pressure regulator (integrated in fuel pump unit) malfunction
*

Fuel pump relay stuck closed
*

Fuel leakage from fuel injector
*

Restriction in exhaust system
*

Erratic signal from eccentric shaft position sensor
*

Improper MAF sensor installation
*

Improper fuel injector control operation (abnormal signals from MAF, ECT, front/rear HO2S and IAT sensors to PCM)
*

Knock sensor malfunction (abnormal signal to PCM)
*

Contaminated MAF sensor
*

Improper engine compression

o

Engine internal malfunction
o

Abnormal engine oil condition (viscosity, deterioration)
o

Low oil pressure
o

Excessive fuel pressure
o

Metering oil pump malfunction

+

Leakage or clogging in oil pipe
+

Leakage or clogging in oil nozzle

zoom44

POSSIBLE CAUSE

Eccentric shaft bypass valve malfunction (stuck open)
#

Improper cooling fan control system operation
#

Thermostat malfunction (stuck open)
#

Improper engine coolant level
#

Improper ignition timing
#

Weak spark
#

Spark plug malfunction
#

Brake dragging
#

Low tire pressure
#

Clutch slippage (MT)
#

Improper ATF level (AT)
#

Improper A/C operation (A/C cut-off control does not operate)

Rotary Rasp

iTrader: (2)

so what you're saying zoom44 is that we should just give up?

snowboarder4eva

I think you're all driving your car poorly.
I've had the car for about 2 years and I get on avg. between 18 and 20 mpg. I floor it once in a while just for fun, but that doesn't do anything. I do way more "city" driving than I do highway.
On a road trip I think the best I got was 22 mpg, but my car was loaded down with stuff.
But for normal every day driving, I just try and keep my rpms low by upshifting.

Howard

I have not discussed milage on this car for almost a year and a half. I was involved in a series of threads and spent a great deal of time trying to find out if the mileage of my car could improve.

I get in town about 13 mpg. I have only 15000 miles on the car after two years.

The dealorship did test my car and were able to get an average of 16mpg in town and on the highway.

They were not able to find a solution.

Mazda even shiped my computer to themselves and tested it and shipped it back and they had no comment.

I ownded a car at one point that had a 400 plus cubic inch engine and dynoed at over 500 hp and it got 14mpg

If I granny drive this car I can get 15mpg in town.

If I wanted to drive that way I wouldn't own this car I'd own a Prius.

My conclusion.
The milage will not change. For some reason it gets worse mileage then cars with more Hp. Many claim to get better milage. I am not going to do anything about this. I love the car and would not trade it for any car of costing any where close to it regardless of the mileage or hp. The only car I would trade would be a Porsh costing 60,00 and that is not happening. I will live with this and accept it unless Mazda finds a solution. I am not angry at them They built a wonderful car that has a flaw.
All cars have flaws.