sambo

i just purchased a rx-8 2005 model - type E . it has been driven 17259 kilo meters .

but the main problem i am facing , that it is having extreme octane .

per liter , it barely runs 3 kilo meters .

is it normal for mazda rx-8 ?

or , is there any way to make my car more fuel efficient ???

plz help me out .

Methanoxide

So you are getting less than 100km to a tank of fuel?

Huey52

iTrader: (2)

"Extreme octane?" Although 93 octane is best for maximum performance, it will run fine all the way down to 87 octane (ECU will auto-retard the timing to protect engine from knock).

18 mpg is typical (7.65 kilometers per liter). The rotary is a known poor fuel efficiency engine.

Not much you can do other than the typical "drive like an old lady", but that's not what this vehicle is about.

3 kilo's/liter is exceptionally poor however. Look to replacing your coils and sparkplugs as you may be getting improper ignition. Next would be to have your fuel injectors cleaned. Low compression could also be a culprit (engine/drivetrain is still under warranty for same).

sjschutz

There is one way...




Sell it to someone who researched the car beforehand and knows that fuel efficiency is not a sports car's selling point.

alnielsen

iTrader: (4)

There is nothing wrong with a person trying to seek better fuel economy from their car. It is a valid point of discussion.

RogueTadhg

1) Make sure you get your tires inflated to the highest-rated for the tires.

2) Low resistance tires also help.

3) Other than that, it's about how you drive the RX-8. You can dog the **** out of her and get low milage, i've gotten higher than 22 when I drive like I was driving a "eco" car. Slow accel, shifting it into 6th as soon as possible, braking lightly.

4) Try to get all the trips in one shot to conserve gas.

http://www.tirerack.com/landing/fuel_efficiency.jsp

As far as swapping engines... Most do it for power, but i've heard (on this forum) that someone swapped in a corolla(?) into their RX-8 for mpg.

I've also seen about reducing the size of the engine to help get the highest MPG.
http://www.rotaryeng.net/RX8-TC-eng3.html

...Just make sure you do ride the rx-8 hard. Carbon buildup and all. I usually rev it hard off the line in second gear to the beep. Once a day.

ken-x8

At 7 mpg, I'd say the problem is more than just tire pressure or driving habits. Huey's last paragraph looks like the right path.

Ken

RX8Soldier

iTrader: (24)

^yup.

OP check the usual (plugs/coils, MAF/eccentric shaft position sensors, Cat converter, etc)

nycgps

iTrader: (1)

i would say he should have know before he got the car. And he should know that 3 kilo meter per l means something is wrong with the car. So instead of wasting time to ask such question, he should just have the car check by someone.

wrightcomputing

iTrader: (5)

If you do a lot of highway miles, driving behind someone will increase MPG, do not tailgate but from a safe distance you will still reduce air pressure in front of the car. Mythbusters showed that at a safe distance behind someone you can save about 30% of your fuel, something like that anyway its a while since I saw that episode.

8 Maniac

iTrader: (1)

That was a really intelligent post. It's not like he's complaining about 17-18 mpg. 7 mpg is absolutely not normal and I'd imagine a lot of us would never have bought an RX-8 if that was typical mileage.

05rex30

I would also try seafoam

Brettus

iTrader: (2)

before asking any more questions - please verify what you are actually saying here .

You fill up your tank with say 55litres and get around 160kms before putting in another 55 litres - is this correct ?

REDRX3RX8

I'm no expert, but you're not even funny.

NOBODY can save any mpg related to the air from the vehicle in front if you value your life or your paint.

Yeah, you can save some riding in the vacuum 20 ft back, but its penny wise and pound foolish ( Think Ben Franklin if you had any education).

At the safe distance its not enough to ruin your eyesight for the road.

YaXMaN

I've seen this problem before, and it's usually caused by a bad regulator.

HiFlite999

iTrader: (2)

Interesting. More like an entirely new engine design, unless one wants to swap in a 35 hp rotary with zero performance.

YaXMaN

Yah. The author of that page has a just a bit too much time on his hands. Dude needs to get out more.

Grace_Excel

iTrader: (5)

Hmmm, but you're sucking in hot air from the car's exhaust you're trying to draft don't you want cooler air? That's why it works in a closed circuit at speeds more than 100 MPH. But at a speed limit?

monchie

For the reason of this question, the op did not realize that the rx8 has poor fuel economy. Complaining about it may solve it or not. The only way to save from fuel economy is to get another car with good fuel economy...yeah, that's it.

Bigbacon

iTrader: (4)

MPG seems so hit and miss though.

I used to get a solid 310 miles for the gas light would come now. 2 years later, I am lucky to get 275. Car has had compression checks, new plugs, wires, coils, etc. Has never gotten better.

Having the AC on makes it even worse.

I am normally getting about 265 miles on a tank before the light comes on.

And before anyone asks, I don't drive like a maniac but also don't drive like a grandma and always drive it hard at least twice a day.

Mindgarden

I once had a 1972 ThunderBird with a 460 cu in (7.5 L) V8 ... that car got 6 mpg, was about 18 feet long and weight like 4800 lbs. I would say your 8 has some issues if thats the mpg you're getting.

REDRX3RX8

I get good mileage like 310 before the light comes on or 23 mpg @ 80 mph on my 2007 6spd auto with 27k miles.

I've seen lots of your discussions, but do you premix, and have BHR coil upgrades?

You should get 23-25 on hwy unless you have lots of miles and are losing compression.

alnielsen

iTrader: (4)

When my car was new, I got 12-13 mpg. 3 engines and 70K miles later, I now get 18-19 mpg. Last fall, I managed to get 300 miles before filling up (about 22 mpg).
Automatics get better mileage than manual models.

RIWWP

iTrader: (2)

It's interesting how few of you are reading the posts that already exist before posting again.

The OP's car has something wrong with it. 7mpg is worse than full WOT track mileage.

Given that, the OP isn't looking for hypermilling techniques, he is looking for help on what is wrong. Some suggestions in that direction have been offered, but plenty of you are giving what can be a 1-3mpg bump, when he needs an 11mpg bump.

Also get your brakes checked to see if one or more of them is partially engaged or won't fully disengage.

russ

That is really a cool idea but the rest of the engine would need to stay thermally stable so that the two main rotors could then start back up in an instant and match speed.

Who am I fooling, pedal to the floor in low gears, just in case I need to accelerate. That's my cruise, and my gas mileage shows it. I did hit 18.3 on my first real highway trip of any distance. Had a lot of fun and isn't that what it's really about?!?

Back on topic, definitely something wrong with the car to get only 7 MPG, I haven't even been that low! (14.5 is my lowest).