Pavehawk

Mine's been running anywhere from 16.7 to 20.0 through 2700 miles.

Spf006

Something I've found interesting:

Up until last weekend, I've been experiencing between 14-17 mpg even in intercity driving...up through ~5000 miles.

Last weekend I spent two days driving the car HARD around VIR at the Mazda Drivers' event. I don't even want to think about my mileage during the event, however...

On the drive home (~300miles from Danville, VA back to B'more, MD) and EVER SINCE, i've been experiencing 18-22 mpg on the same daily commute between Baltimore and Washington, DC.

My conclusions: the engine wants to be run and possibly doesn't really "break-in" until it has been run hard. Those seals might need a good jolt to seriously seat them.

Anybody else, perhaps with technical expertise, care to weigh in on the possible reasons behind this?

Cheers,

PhineasFellOff

As promised, I have just posted a thread with the incredibly high mileages I got from 20 tanks during my trip across the country.

Please check out the thread in the Discussion forum.

Rotary Nut

Turned the big 5K today.! Whoo hooo!

I hope to see a marked improvement on this new tank.

Rotary Nut

Updated.

Also changed the oil and the brown condensation was no longer present on the dipstick!

Ole Spiff

To SPF006

After reading your post, I was thinking perhaps the computer in the car is much more involved in day-to-day driving than might be expected? It may have nothing to do with "break-in" but may actually be a constant monitoring of driving conditions by the computer.

I've always gotten decent mileage with my 8 (I bought mine in July of 2003) but I've always driven it "vigorously" and never babied it. Did you drive "for mileage" before this weekend event? Maybe the rotary 8 being unlike any other car, is also unlike other cars when it comes to mileage and driving habits. I know that rotaries put out much more heat than piston engines. It's possible that the computer cools down the catalytic converter with fuel if it doesn't sense enough 'action' or intake/exhaust flow.

By driving it hard like you did, the computer 'read' the right amount of flow of intake/exhaust and backed off on fuel richness.

I would be curious to see how many who get poor mileage granny drive....

Just an idea....

stanfordcole

I was getting 16 to 17 miles per gallon mixed driveing when I first got my 8. It now has 4500 miles on it and I am averaging 19 to 20 with mixed driving. I have a 5 or 6 mile commute to work. Its the only time I have felt like I live to close to work. I would love to have a little more time to enjoy driving the car while commuting to work. I drive it conservatively alot of the times but I don't hesitate to get on it a little when I feel the desire. After all thats what I bought the car for. I can't complain about 19 to 20 and if it goes up more then great. If not I'm happy with it.

Chris in MD

Went on my first road trip - about 800 miles roundtrip. Car now has over 2200. Also got my record 21.69 MPG with Shell 93 - not very judicious with the throttle either, breaking 100 mph several times and probably averaging around 75 most of the tank.

rchaud98

How are you taking these measurements? Any car I've ever driven, the gas needle bounces by an 1/8 both up and down so how are you coming up with decimal numbers for mpg? Is it the same as how you guys say the rx8 goes 0 to 60 in 5.5 seconds by people looking at their watches and counting out loud?? :D

rchaud98

I believe people are just making up numbers as none of these readings are accurate. Hell what if you live in San Francisco and are driving downhill yourf fuel gauge won't be accurate. You want to take REAL readings.


FILL the tank ALLL the way up till it's completely topped off and then fill a seperate container like the ones lawn mowers need and drive around till you run COMPLETELY out of gas and measure your distance and divide by fuel tank size and voila you have your true accurate number.


Kthnx

MEGAREDS

My readings are very accurate and there is no need to be picky about the way you top-off. Over time the averaged numbers become very precise. Here are the updated numbers; I'm getting just under 18 mpg with mostly suburban-type driving.

rchaud98

range of 24 to 13 is not accurate.

Doo dee DEEET. Please hang up and try your call again...

PhineasFellOff

Your method of running the gas to empty won't work because, as we found out in other threads, the car will run out with .8 to 1.0 gallons left in the tank. This means you can't just run the tank out, jot down your miles, and divide by 15.9 gallons. You'd still have to get to a gas station and fill up. As always, the amount of gas you fill up tells you how much was used on the previous tank.

MEGAREDS

rchaud98:
Outliers have no affect on the overall accuracy of the data but can skew the data if you use a small enough set. That's why its important for people wondering what their "true" mileage is to take a large data set, not just one tank.

If you distrust the average, use the median -- in many cases a better way to describe trends in a data set. It is the value of the middle observation, after the observations have been ordered from smallest to largest. In other words, 50% of the observations are above this number, and 50% are below, that is why it is also called "the 50th percentile." In my case, it is the average of two tanks, the tank on December 5, 2003 (18.1mpg) and March 27, 2004 (17.7 mpg), meaning my median is 17.9 ---> precisely the same value as the average.

rchaud98

True..

To me the rx8 body is the perfect car (handling,looks) it's the engine that's dissapointing... I hope the 2005 model fixes issues such as lost HP, Flooding and mpg. Once those are fixed I'd easily and proudly call the RX8 Car of the year!!!!


http://story.news.yahoo.com/news?tmp..._ge/gas_prices


U.S. gasoline prices climbed another 3 cents per gallon in the past two weeks on the strength of high crude oil prices, tight capacity and soaring demand, an analyst said Sunday.


geeze....

wayneside

i doubt i get better than 15 mpg...even on a 5 hour drive i had to refill. my 350 has much better gas mileage but the 8 is sooo much nicer to drive daily...

mysql101

Prior to M, my first tank got 17.x, my second tank was 16.x mpg.

I then got the M flash.

With about 70% highway I have 18.7 mpg on that tank (229 miles, 12.210 gallons).

Still hard to say with my numbers since I've not fully broken in the car, have yet to have an oil change, and my driving the car is pretty random.

I'd like to see around 20-23mpg eventually.

Ah, modest goals.

Chris in MD

rchaud98 - not sure what you are talking about. You fill up the tank, drive for a while, fill up the tank and then divide the miles by gallons added. I can show you the calculation if you want. Not very scientific and probably not consistent enough for lab work but I guarantee with a large enough data set you will get a pretty good average - statistically relavant within a couple tenths.

If you're so concerned about gas mileage buy a Honda Insight dude - 3 cylinders and 66mpg :D

ArvinC

...trip down to the Eastern Shore of Delaware and Maryland. Trip was 142 miles one-way and I averaged 22 miles per gallon in very relaxed driving. Average speed was 60-65 miles per hour and had no traffic what-so-ever. I do not believe I have the L-flash as yet...definately know I don't have the M-flash! This was the first long-trip I took in my car, but attribute it to finally being broken-in as I turned over the 2500 mile mark.

Arvin

Puppy1

I'm consistantly getting 21mpg in mostly city driving. I have over 16.5k miles and love my car more and more each day. My only complaint is about the service department manager at the dealer in Santa Monica.

bowman

I have been tracking mpg for my current car for the past 3000 miles.

I fill the tank and use the gallons added as the amount used. IMO gas guages are not accurate enough to measure mpg.


As to using the average, median, etc, I ran these numbers over my data.

NOT AN RX-8

Mean 29.62 (aka average) w/ Std Dev 1.23
Mode ~29
Median 29.74

NOT AN RX-8

elite

got the flash when the car was about 200 miles so i dont know any more then Im getting 175 to a tank. the performance is laging and i am super pissed but the dealer is saying everthing is fine. this past take ive been doing alot of shifting under 3800 and still gonna get the same 175 for about 13 gallons......

i dont know what to do.....my dealer doesnt eem to say anymore then wait 5000 miles and itll get better..BS!

rchaud98

What are you getting so uppity about? Jeeze I'm not the one that paid 30,000 for car that puts out 175 whp, gets 14 mpg goes 5-60 mph at 7 seconds and floods without notice.