13 miles per gallon??!!
 

I know I know.. more gas mileage concerns.. I've been following the forums for a while now.. I've got roughly 500miles on the car..
and for the 2 and a hlf tanks of gas I've used.. I am getting 200miles to the TANK! I just received the Road and Track on the 8 and they est a 280mile to the tank. Is anybody getting the same gas mileage??

- Driviing habits - Keeping the RPMS below 5 grand! - Few spurts to 7.. and thats it. - Using 92/93 octane also - Short highway trips (10miles) to work and to school and back.

I've read the other posts, but have not heard nor seen anybody posting how many ACTUAL miles they are getting to the tank, I know its a "sports car" and whatever else ppl have said. To me, for 13 mpg I should be driving a Viper.

My driving habits seem similar to yours and on my second fillup I drove 231 miles before the low fuel light came on, averaging about 17.5 mpg...

yea im getting around 13 mpg around the city. i can actually see the fuel needle going down when im driving from point A to point B.

The worst mileage that I've seen so far, in 2700 miles, has been 12.8 MPG and that was all highly spirited driving. I routinely see 18 MPG with my normal mix of city/highway driving with a moderately heavy right foot.

?
 

Am I driving wrong?? Or is there another issue here?? Could the gas station of choice be a problem?

Are you idling the engine a lot (e.g. on cold start)? That seems to burn a lot more in a rotary than in a piston engine, also short trips seems more fuel consuming . Those are the main contributers to my fuel consumtion. AC-headlights-stereo makes only marginal difference.

/Elak

the gas really sucks. I am filling up every other day. I don't drive too hard. I think I'm getting 14 or 15 mpg. This is the only problem I have with the 8. I LOVE THIS CAR

actually on cold start *as cold as its gonna get in Florida* I'm doing like the booklett states/ keep at 3k etc.. / It just seems like the car is EATING the gas..like it has a hole in its mouth.. Just wondering if there is a "problem" in the gas department *excuse me* in the car

Alas, your experience is the same as mine. I've also watched the mileage poll thread - We seem to be at the bottom of the curve for mileage.

I can not get 200+ miles from a tank. On the first tank I got 15.1, then 14.5, then 13.2! I have not pushed the engine hard - never above 6k to date. Most of the driving is 20 miles each way home to work on the freeway.

What's weird is that for the first tank, the average RPM was higher than the last tanks - yet the mileage is dropping. I am very concerned about not only the lousy milage but also the trend of getting worse each tank. Note that each tank has been the same premium gas brand (I'm trying to keep the variables to a minimum while I figure out what the issue is).

This is the only serious thing I have to complain about the car (now complaining about the dealer is another matter entirely).

I talked to Mazda cust service earlier this week (as a result of my latest dealer experience) and asked what could be done - they suggested that I have the dealer "run a fuel consumption test" - so I plan to have that done (what ever that is - hopefully it is something other than having a mechanic put 200 miles on the car :( ) - just as soon as I find a dealer that I think knows anything about a rotary engine...

This week I've been driving like it was an electric car - all shifts between 2k & 3.5k - any lower and the car might as well not be moving. I've also refused to run the air conditioner - with all this I am at about 175 at 1/4 tank... Ok that's better but overall I think this is situation is crap. I'm doing freeway driving - 13mpg is 72% of the city estimate and only 46% of the highway estimate. That is outside reasonable tolerance for an EPA estimate IMHO.

The car is either going to get better or I will seriously start considering the details of forcing a return of the car (which I know will be a huge hassle - hence my careful record keeping and the motivation behind identifying the issue to Mazda USA early).

Frankly, this is a much bigger issue to me than the HP stuff from other threads.

At < 200 per tank, as much as I like the car, it is simply not very practical as a daily driver car.

Hell, If I really want to burn fuel, I go run my boat around (at least a full load there gets me 1000+ miles of fun - even if a full load is 450 gallons - at least I'm moving 30k lbs while using the fuel). :D

Dave

Please don't flame me over this comment, but are you guys sure you aren't driving down the interstate in 4th or 5th not 6th? I've done it (for a short time) cause it really doesn't make much of a different noise and I was paying attention to smthg else at the time (like heavy traffic).

I'm having fun flooring it regularly, certainly not babying it, and I've got 17.5, 18.5, 18.3 three tanks so far... so like 235-250 miles a tank no problem. If I really paid attention, and took a trip (which i haven't done yet), seems like 20+ shouldn't be a problem.

Dang, that's one heck of a boat! 3 miles to the gallon, does it have a Rotary too :D

I was seeing about 200 miles per tank the first fillup. Second one half a tank went in 100 miles, but then I started to shift usig the guide in the user manual (about 3KRPM per shift) and cruising about 80MPH, I have gotten an astonishing 200 miles from the rest of the tank. This was all highway driving though with about 40 minutes very light crosstown traffic. Car isnt as fun this way, but mileage is way better. Got 540 miles on the car so far.

Edit: Forgot to mention that I was running AC a lot the first tanks icne it was raining here all the time and with the warm air, it gets real humid, real fast. Last few days have been nice so barely any AC usage, mainly for defogging.

If my next fillup actually runs me for 400 miles, I will be MOST pleased :D This weekend my driving will be light traffic and some highway so it will be a best case scenario. Tank after that I will try to stick to heavy traffic. Visit my clients in downtown Miami and see how that goes. I probably wont be able to arrange enough visits to make it all traffic driving, but if I time the drive home right I will hit rush hour and thats just as good.

13 mpg is way too low. Shoot, even my 25 year old 4bbl carburated 12A rotary gets 16 mpg in the city and 26 mpg on the highway @ 75mph. That's with an antiquated ignition system and me laying on the gas all the time. You guys need to take the car to the dealer and have them figure it out. Idling is where the Renesis is supposed to mop the floor with previous rotaries in terms of fuel consumption.

Just to add insult to injury, there is a guy on the rx7club.com board who has a bridgeported 12A and still got just over 20 mpg on the highway.

Something ain't right here folks. Personally, I think the piss-poor gas mileage and the missing 20 horses are closely linked.

On my drive from Ft. Lauderdale back to Buffalo (after break-in) I did notice steadily increasing mileage and my last tankful took me 289 miles at which time the fuel light came on for about 4 miles before I filled up. Granted, this was 98% highway, but still gave me ~23 MPG (12.6 gal - which I find strange that the fuel warning light comes on sooner than expected - well before hitting E on gauge. I thought it comes on after about 14 gal. leaving 2 spare after warning.) Just some food for thought. Since then i seem to be getting about 230mi/ 12 gal = 19MPG of mostly city (suburb) driving.

Well, I like it! It's a 36 ft trawler (Island Gyspy 36 Europa for those into boats), displacement about 30k lbs, powered by twin Ford/Lehman 135HP inline 6 diesels. Total of 270 HP...

A single Rotaries would be MUCH smaller (but a performance disaster as low RPM torgue really counts when driving a prop).

Now ya got me wondering - is there any such animal as a diesel Rotary? :eek:

Dave

No flame from me -
yep, I am sure of the gears being used (at least since the first tank) as I've been paying attention to see what I can get from the car - and it just keeps getting worse... I'm frankly puzzled - I read the other posts about 20+ and wonder if we're all talking about the same car.

Dave

I'm on my 3rd fill up and approaching 600 miles on the car. The first tank was great, I recorded 23mpg. The second tank was a whopping 16mpg. I can tell this third tank isnt going to do very well either. For reference I am driving the same route with the same conservative driving style( still breaking it in - can't wait to floor it :). The ironic thing is my TII regulary posted between 20-24 driving the same route.

weird
 

I find it very uncommon that some are getting good mileage and others are not.. The first half of this tank my shifts have been no greater than 4 grand and I am still at 100 miles (roughly).. So I figure I might as well drive hard once I talk to my dealer.. Not to mention the service tech at the Mazda I bought it from *Fairbanks in Longwood- Is 2nd place in the US/ not too shabby. but with all consideration, will continue to monitor the rest of this tank, and will be contacting Mazda shortly! Thank you for your replies! Helps to know others are getting the same, could use for backup if need be! Will post what the results are.

Joe

weird
 

wrong button

Re: 13 miles per gallon??!!
 

8th, my driving habits sound just about like yours. I'm getting between 15.5-17 mpg for the past several tankfuls. I was disappointed at that, but just finally decided to not worry and enjoy the car. At 13 mpg I'd be real upset. It's strange how all our different cars are showing such variance.

I guess I gotta read the owners manual. Does it really say to shift at 3000 rpm? I shift a little higher, 3500-4000. It's just starting to get into its torque band about there, so at 3000 and below you're feeling very little power and the car isn't any fun at all. If that's how they estimate their EPA mileage I'll never get there.

I have to agree that my mpg is getting worse not better. But I have to concede I drive this car like I would drive any other. I can't drive like an old granny, but even so the best i've ever recorded was 17.25mpg and hit the mid 12's a couple times.. I have averaged 14.5mpg over the course of 1200 miles.. pretty shitty I suppose.

I'm averaging between 25-26 MPG in the EVO. :p

My fuel mileages are actually improving. After 9 fillups and 1770 miles, my fuel consumption is 18.8 mpg. On first tank I drove conservatively and got 16.3 mpg. That was the worst one. It has since increase steadily and has been as high as 20.9 mpg. After 600 miles, I'm shifting around 5k rpm and I'm not holding back in my driving. Even on the last fillup when I had a dozen WOT acceleration runs and pegging the rev limiter, the mileage was only 17.6 mpg. So it's strange that some of your mileage are getting worse.

I must drive like a maniac and not realize considering the sizeable difference in mileage. Hmm.. It just seems strange to always have in back of your mind to "manage your revs", drive slow etc..

Oh and I did, in my estimation, kept it easy the first 700 miles of driving, but afterward I been driving as normal (what ever that might mean). I will look at my average up to 700miles and then after. I'm hoping that reports of improved mileage as the car settles in and possible ECU remapping becomes true at some down the road. Happy driving all!

My mileages are improving just like Good Duck, almost exactly the same numbers. From first tank about 16 mpg to now 19 mpg. I have 1400 miles on my car.

Mine also.... first tank for me was around 15mpg, and it's grown since then. I neared 18mpg last fillup. I think I'll break 20 eventually, but given I do *all* city driving... it's a tough task to accomplish.

Good news: Reported MPG @ 417 miles
 

Well here is our MPG so far, as reported by my wife. Car has 417 miles on it.

1st Fill up - not documented

2nd Fill up - 20.0 MPG - This is all city driving (Tampa). Wife has NEVER taken the car over 4500 RPM's.

Outstanding MPG for city driving. Better then the reported EPA. So to all the doubting Thomas's, this definately tells us that if you keep your foot off the gas (<4500 RPM's), and drive conservatively, you can at least meet the EPA. But of course you are missing out of some of the fun of taking this baby into the upper RPM's. :D

She'll be traveling to Ft. Myers, and back, this weekend (120 miles one-way) and this will be all highway mileage. I will report back when she fills back up after her trip.

Re: Good news: Reported MPG @ 417 miles
 

So she says... :D

Mark,
Make sure to remind her not to stay at a steady speed/RPM for any extended period. At least until the break in is over. In other words no setting the cruise to 95 and kicking back in the leather recliner :)

An update - I just filled the tank again - this time I got 14.4 MPG - this from "granny driving" (and not the type from Pasadena for those old enough to remember Jan and Dean) and not using the air conditioner.

The extra mileage is not worth it to be hot and sticky. I'm sure hoping that it starts improving (I have about 650 on the car now).

Talked to the dealer about the "fuel consumption test" today = he's checking into whether his mechanics know what that is and how to tdo it - at least he was up front about their level of rotary expertise.

Dave

Mileage report
 

Just under 1k after 5 weeks. My commute is short and I have not taken any trips over 60 miles. I now document my fuel usage after taking note of the 8's hearty thirst. 14 -15.5 and 16 are my MPG results so far.
I love the performance and feel of the car but I sure wish it didn't drink so much!
Maybe a 1000 mile tune-up will lean it out. I doubt it.
TDS

1200+ miles and 15.6 mpg on the last tank of combined driving.

Re: Re: Good news: Reported MPG @ 417 miles
 

Funny stuff. I trust her. She knows I'm pretty adamant (bitchy) about "my" car and how I want it treated during the break-in period. When it was time to shift, she used the tac and did not rely on feel or sound. She's one of the best female drivers on a manual transmission I have seen.



Tom,

Thanks for the advice, but she knows since I told her earlier. Before the first fill-up (which she didn't document) she had about 50/50 city/hwy driving. When she took it up north to our relatives in Bushnell, on I-75 she didn't use the cruise at all, and varied the mph about every 10 minutes of so.

I real curious to find out what the MPG will be after her trip to Ft Myers. It should be about 15/85 city/highway. I told her to fill-up immediately after her trip, so we can get a better idea of the hwy MPG.

Correct me if i'm wrong, but there was a whole other thread about this which came to the consensus that a rotary (or any engine at that) will get its best mpg at the rpms at which the engine is running most efficiently, and on a rotary this is about 6000, which might explain why some of the granny-type driving during break-in would yield low mpg. I however have never yet bothered to calculate the mpg on my car.

wtf 6000??? no way. i would imagin keeping the car at 6000 all the time, would yield even worse gas mileage

Exactly. MPG's will be lower. If you are keeping the car at a constant 6000 RPM's, you need to upshift son.

This wouldn't apply to overall mileage averages, but I noticed in my RX-8 that sometimes the gas pump nozzle auto-shutoff activates well before the tank is full. I know you're never supposed to completely top off the tank, but I tried last time just to see, and I got 3 more gallons in. If you have one "fill-up" showing unusually low mileage, this could do it.

I'm consistantly getting 19+/mpg after 5 tankfulls. 80% city driving in stop and go in L.A. traffic. During the break-in period I never exceeded 4.5k rpms. Now I rev to 6-7 all the time occasionally hitting 9+k.

I'm taking a road trip this weekend. We'll see what kind of hwy only mpg I'll get.

I have exactly the opposite experience - when the nozzle clicks off in my car, I can't squeeze another dime's-worth in there.

I have this station I ALWAYS fill up at, and am very familiar with which nozzles I like, etc.

Even parking the 8 on a downhill grade (slight, away from the pump, and downhill to the left front), I can get a good 2 - 2.5 gallons in after it's clicked off for the first time. It requires a little patience, but I need it to keep accurate fuel mileage records (it has to be the SAME full every tank).

My wife's Volvo does the same (the Ford influence?) - quite annoying.

There is either a big variance is these engines MPG or some of us just don't know how to calcualte it.

1) fill it up (with gas)
2) reset one of the trip mileage indicators
3) drive car until more gas is needed
4) stop and "fill" it with gas"
5) note how much gas it took
6) note how many miles are on the trip meter
7) (using a calculator) divide the number of miles by the number of gallons off the pump.

example: 211 miles/ 13.27 gals = 15.90 :(

I kid here but I seriuosly I have to wonder how many people just take a quess and figure it this way:

1) I drove to work twice (I went about a 100 miles)
2) used less than half tank
3) it holds about 15 gallons
4) let's see 7 is about half of 15
5) 5 is less than 7
6) 100 divided by 5 is 20
7) 20 miles to the gallon WOW

I've been carefully measuring the tank/gauge relationship. I waited until I'd used 1/4 tank, and filled it up to see how much it would be, then repeated this for 1/2 and 3/4 to make sure it was accurate.

I have noticed that even with conservative driving the first half seems to go faster than the second half, although I have no idea why.

Assuming that the 1/4 ... 1/2 ... 3/4 are accurate and that you drive the same way in the same conditions (speed, traffic conditions, temperature, humidity, barometric pressure etc). Then the difference would be due to the added weight of the fuel. 1 US gallon weigh between 5.8 to 6.5 lbs so a full tank (16 gal about 100 lbs) so a half a tank is 50 lbs. I find it hard to believe that 50 lbs could make that much difference, but then again...

I'm convinced that driving style has a lot to do with the mpg. I have about 2300 miles on my car, and I am getting about 21 mpg. My driving consists of 80% hwy driving.

Overall, I'm pretty happy with these numbers because my 2nd gen. RX-7 got about the exact same gas mileage (and I have 100 extra HP in the RX-8). The HP is not exactly free however, because I have to pay almost $1.50 a gallon to feed this one (ouch!).

A lot depends on driving style on any car.

For example, my current car is rated at 18 city, 26 highway and I regularly get around 23 MPG mixed and 28 highway.

How? My driving style, and especially in the city, my shifting patterns. I tend to shift from 1->3->6, with the 1->3 and 3->6 shifts each coming at right around 3K RPM.

Try "short shifting" for a tank with the goal being to get the tranny into 6th as soon as possible without lugging the engine and see what you get for MPG numbers; you may be pleasantly surprised...

lol TJRX8. I feel same way. 20mpg city??? Can't possibly be the same car as my RX-8. I am getting 13-16 mpg w/ 1050 miles on the car & about 80% city, 20% hwy.

Hard to complain about the mpg w/ this car as otherwise awesome as it is. But this is kinda ridiculous. Somethin's definitely amiss....

With an EPA estimate of 18 city, 24 highway, why is something "definitely" amiss? Yes, it's a bit low, but the Mazda web site, among other places, states:

ok,ok - calm down billy. Maybe I used some strong words there.
Let me clarify my thoughts on this issue...

I think whats got people disappointed here is that, with the EPA ranges that have been provided - alot of people are sitting at the very low end of those ranges, or even worse - like me - sitting UNDERNEATH those ranges.

Another thing is the fact that w/ all the re-engineering Mazda put into the Renesis, their resulting fuel efficiency seems as low or lower than previous rotories.

Lastly, from the posts I've seen, there's a pretty wide variance wrt mileage. Granted, some of that is to be expected due to driving style defferences. But, we must entertain the possibility that some of these motors might have issues.

So how did Mazda come up with the 20/30 MPG estimates they had on their website for most of the pre-order period? That looks to be about double for what many people are getting in the real world? :confused:

Below 13!
 

Argh - I used the air conditioner a bit this weekend - and the air condition button appears to activate a hole in the bottom of the gas tank.... At 92 miles I was below 1/2 tank! I filled it this morn - mileage was 12.62 mpg - easy driving, but air on.

I guess I'm gald I got the nav so I can find gas stations - what I don't understand is why the nav is not interfaced to the gas gage so that the car can just redirect you (every couple of days) when it reaches 1/4 tank..... :(

Dave

I have never turned the AC off. On my first ever tank I got 15.5mpg, on the second I got 19mpg. Now I am through break-in I will hit 8k-9.5k rpm about 30 times a day in first/second gear - lets see what happens.