schainrx8

hey guys!

i have had my rx-8 since feb and average 13 mpg city and 18 hwy. this is a lot lower than the EPA. is there something wrong with my car (no mods) or is this a normal thing. i drive sporty but not crazy? thanks for the input!

Sigma

That's about average, honestly. Many people get quite a bit worse than that.

pcimino

Holy cow! Another mileage thread. And if you want to get the EPA mileage, you need to drive like my grandmother in her Reliant K car.

I'm actually trying an experiment this week where I'm attempting to keep the revs under 4K and stay under 60 mph to see how much my mileage might improve. I am failing miserably. Partly because it is PAINFUL to drive this car like an econo-commuter, it wants to go. And also because every person on their way to work drives like it's NASCAR. I'm now the "moron" in the right lane every one has to pass at 70 or 80, including the landscaping trucks with their 45 MPH rated trailers fish tailing behind them. Thankfully I'm almost done with this experiment. Tomorrow I get gas and calculate my mileage.

Then it's back to driving the car for the reason I own it: for fun!

mikeschaefer

you can go a week before filling up? :p

Psylence

12-13mpg around town, 19.2 on the highway. Not thrilled, but I can deal..

Wanna hit EPA numbers? Set your cruise at 48mph on the highway, for starters

zoom44

that is just not true. most people do not avg 18 on the hwy. most are getting 22 and many have shown 24 or more is not that hard either.


explain the 18mpg highway trip. when did you get gas. how many miles before you got onthe highway. how many miles onthe highway. how soon after you got off the highwat did you get gas? how many total miles between fills? how many gallons did you fill with?

2nd avg 13 mpg in the city could be a problem with the car or the drivng conditions. do yo sit in alot of traffic all the time? lots of stop and go? go out for lunch everyday by driving a half a mile? what gear do you use the most in town. at what speed?

zoom44

ive shown to several members that the 24mpg highway is obtainable with cruise set at 70. cruise set at 48 for the same drives would have probbly netted me 27mpg or better.

Glyphon

other things that can cause poor fuel economy...under inflated tires, tires that are out of alignment, flooring it on every start, prolonged startups before driving, terrain (is it hilly or flat), amount of traffic (both length of time and traffic density), driving with the windows down on the highway, reving to 6k before shifting everytime...

zoom44

bad mpg can also be caused by stuck thermostat that leaves teh car in open loop

here read this mpg site

dmp

My car has only ONCE gotten the magical '20mpg'. Even on my last trip (last weekend - probably 5 hrs straight driving) my car got 19.94mpg.

Keep in mind since the R flash last month, I get about 30-40 miles more per tankful, than on the M Flash.

Sigma

Now that's a pipedream if ever there was one.

Find a thread where even even 5% of people claim to get 22mpg+ on the highway, let alone greater than 50%.

Sure, people with bad mileage are more apt to post about it. But the number of people claiming to get over 20mpg is so small there's absolutely no way you could reach a conclusion that "most" people get over 20mpg on the freeway. In almost 100 views so far, you're the only one to contest what I said about about something in the vicinity of 13/18 being about average. It maybe a little lower than normal, but it's certainly not out of the ordinary for someone who, admittedly, drives "sporty".

johnnyo

91 octane and i got 21.8 mpg for a 200 mile highway trip
when in town i get 16mpg

Glyphon

i've seen numerous people post that they get well above 13/18 mpg. personally, i'm averaging 18.5 mpg on 70/30 driving with my highest recorded mpg at 23.5.

arrow_choi

I only get 15MPG in city, I tried to turn off the DSC and TCS and have the dealer to reflash my program, but it did almost the same....
Why this car is so much off the EPA numbers? All my other cars do NOT have this issue and I drive them like a normal driver, not grand ma in K car style.

Sapphonica

One more time: the 8's gas mileage SUCKS for a car that has to be thrashed to get into the 14s for a 1/4 mi.

If the 8 was running 12s or low 13s, maybe the ****-poor mileage would be OK.

Most of the gas goes to heating up the exhaust manifold...not a good use for it, IMHO. Also, it sucks as much gas at idle as it does going 55 mph, so sitting in traffic is a killer.

Don't buy this car for straight line performance or gas mileage.

BTW, I have gotten 21+ mpg on pure highway driving @ 73 mph with my whole family & ski gear onboard. In mixed driving (~50% city, 50% hwy), I've never seen over 17 mpg. Just pathetic given the anemic performance of this torque-less dog.

Now that I'm FI, my mileage will certainly go down, but it's no longer a daily driver, so I can live with it.

zoom44

sigma go into any bad mpg thread you want and you will find all the disputing posters posting 22 mpg plus highway. look even saphonica who has sucky mpg states 21+ on the highway at 73 mph.

bottom line if your car cant get at least 22 on the highway at 65mph cruise on windows shut then there is somethign wrong with your car.

Sigma

No, he says the mileage is just sucky for the RX-8 across the board, not necessarily that his is sucky compared to everyone else.

I'll grant you that at perhaps 65mph, only because due to the driving habits of most people who are going to frequent a Forum, most aren't going to drive that slow, so what people here report is going to be worse than that. This poster asked if his 18mpg as a result of "Sporty-driving" was something 'wrong' with his car. If that's something 'wrong', then Mazda has got a LOT of cars to fix.

I never said that 22+ wasn't possible. I know it can be done. I just said that it wasn't from the average. In your own posts about that one time you get 24mpg many people were incredulous that one could get 300 miles before the light came on, and you were out to prove that it could be done. For every person getting 22mpg, there's at least 1 getting 16-18 on the freeway. So, all in all, getting 18mpg is not out of the ordinary and certainly nothing "wrong". Particularly when one admits to driving "sporty", which I would very much assume is quite a bit more than putting along at 65mph. As good as it could be? No. But not necessarily indicative of a problem either.

Tamas

iTrader: (1)

19 mpg with 50/50% mixed driving - I have not driven the car for more than 100 - 120 miles on the freeway in one tankful yet (in almost TWO YEARS ), so I don't know what the 100% freeway mileage would be. However, I'm sure it will be above 22 mpg, based on the mixed fuel mileage. And I just got the REVi + cold air duct (which so far appears to increase the mileage) plus I'm not even on the R flash yet (M here).
If this is how the car will behave, I have nothing to complain about.
I posted the other day how I got 20 mpg average in 50/50 mixed driving in a rental V6 Mustang (not pushed)... The RX-8 is 1 mpg worse than that and at the same time a hell of a lot nicer car.
I feel for the folks who get 13 mpg, but my firm belief is that something must be wrong with their car.

zoom44

that was not the first time i got over 300 miles. nor the last. i do it every tiem i go on a trip which is about 5 or 6 trips since owning the car and probably 20-30 tanks. that was the first time i proved it to other people. we werent even doing 65 but usually 75 or 80. there were tanks when we reached speeds better than 100 and we till got 19 or 20. thats with hard acceleration etc.
getting 18 on the highway avg (meaning sometimes lower) is a problem. either its the driver or the car. but its an individual problem not a problem with the vehicle in general. this vehicle is very capable of getting the epa estimates. 16 around town is still within the epa estimates.

seperating the normal driver from the vehicle is the only way to find out if its the driver or the vehicle.

NgoRX8

iTrader: (1)

When I first had my car, I got 13 mpg driving all city. At 6k my mileage has become 14 mpg driving all city... I don't know if its break-in, but that's all I can say.
Mileage sucks, but I live with it.

scottmhr1

It depends on what you call city driving. If I drive the 8 to work and back only I too get about 13 mpg. But, that is only 2.5 miles away, not enough to really get her warmed up well. Plus in heavy traffic you will burn up gas too. On the few mixed trips of about 70/30 hw/city I have gotten 20 mpg. It's all in how, and where ( how far) you drive. My beater is a old civic, just to work and back I get about 20 mpg, that is a good 5 mpg under EPA. Damn civic sucks ***! Course I do drive that 1.5 sporty, lol.

eclps0

cant break 16s in mixed driving. drove from tampa to ft lauderdale 17 mpg at 80 mph cruise with 2 people weighing in about 280 pounds, Before N flash i was getting 18-19 mixed driving and 22 mpg highway.

DaGnome

Well i've been keeping track of every single gas fillup I've done since I got the car back in Feb.

Now I've been a bit **** about the gas because of all the issues I heard, so I figured I'd use my car as a test of sorts. Always the same gas from the same station (or two if needed) and I've kept track of everything.

It's a 2005 MT model, with the Touring package. No extra mods that would impact any engine performance. I used one of those octane boosters exactly once, and noticed no increase in MPG so that ended right there

There is exactly 5222 miles on the car as of last fillup, and I drive it every day to work. It's about a 23 mile drive, half on the turnpike and half in stop-n-go traffic, takes about an hour (yes it sucks!). For those familar with South Fl... Pembroke --> Miami.

Anyway.. I've filled it up exactly 20 times, always a complete fill up from the time the little light comes on.

Always use Chevron 93 octane gas from the same two stations near my home.

I'd say I drive 'normal', that is not like a grandmother, and not like an aggressive teenager either.

My MPG has averaged 17.5 over the course of the 20 fillups.
My lowest was 14.2, highest 19.5.

Keep in mind the heat down here has been horrible so AC is running all the time, and engine gets extremely hot.

Can't wait for it to cool down to see what effect it has on everything.

Hope that helps.

Ohh should mention that I've never had a Flash done on the car , nor the recall stuff yet (Still waiting for the letter from Mazda). I don't know what flash the car came with but it's an 10/2004 build.

pcimino

I've gotten 21 or 22 higway, cruise. But that's not my normal driving.

My commute is 7 miles each way, half highway and I normally get 17 mpg. If I had a longer commute, the extra miles would all be highway.

Last week I decided to see how good I could do driving conservatively. Never exceeded 65 mph, tried to keep rpms below 4K, etc.

I got my mileage up to 19. I saved a whopping $4/tank ($3/gal gas). $4 for one week of driving, I spend more on lunch, most days. $200/year extra on gas. I spend a lot more on tires.

I gave up the experiment when a hearse passed me. I'm back to enjoying my 8.

If the extra gas, tires and insurance really bugs someone, they should sell the 8 and get a Focus.

apotocki

I got 17.8mpg on my last tank......been pretty consistent for the past couple months. This is with 'mostly' city type of driving (I'd say about a 70/30 mix). I'll admit, though, that I do like to hear the exhaust and frequently take her to 6k for most of my shifts (1-2, 2-3).

I'm not at all concerned over the gas mileage this car gets.....I realized when I bought it that I was buying a 'sports' car, and not a compact efficient machine (I.e. - hybrid, Focus, etc.).....I did not 'expect' my gas mileage to be all that great. Quite frankly, I'm very happy and pleased that it is getting 17-18mpg!