jtimbck2

Bet that title got your attention! I'm one of the folks who was getting average 13-14 mpg in my 8 in around town driving. I didn't complain about it (much), but it secretly drove me nuts that other people were consistently getting 18-20 mpg in the same type of driving (not to mention that the EPA estimated mileage on the window sticker said I should!)

Well, I did something and now I'm consistently getting about 18 mpg in the same driving I was getting 13-14 with before! What I did will probably seem quite obvious to many of you, but it was a revelation to me!

So step right up and hear my secret: I learned how to drive a 6-speed! No, I don't mean working the clutch and accelerator and shifting gears; I've been doing that for 20 years (since I first started driving). I just learned WHEN to shift. I've never owned a 6-speed before -- all the manual transmissions I've ever driven were 4- or 5-speed (well there was that 3-speed on the steering column truck I drove a couple of times when I worked at a grocery store when I was 17, but I digress...)

In a 5-speed, 5th gear is the "overdrive" gear that you never use except on the interstate. In a 6-speed, that place is taken by 6th.
Similarly, in a 5-speed, around town driving is usually in 3rd. It follows that in a 6-speed (at least this one), you can easily row your way up to 4th around town. I was driving with the RPM's too high by staying in 3rd most of the time (because the 3rd gear in the RX-8 is so damn "tall").

As a result of this "shift" in my driving habits, I'm getting about 5 more miles per gallon! Eventually, my new shifting pattern will become second nature to me, and I won't have to continually remind myself to upshift to 4th.

Like I said, this is probably extremely obvious to many people, but it was something new I had to learn.

eclps0

i found out something 2. i unpluged my battery and reset the ecu, well i now have my results. I have increased my mpg by 3 instead of 16-17 i have receved 19-20 i reached 270 miles with 2 gallons left over OMG. I have always shifted at

1-2 2800rpms
2-3 3000rpms
3-4 3000rpms
4-5 2800rpms
5-6 3000rpms

and on highway i dont go over 82 tahst about 4100-4300rpms for about 45 miles a day.

swoozie

Great suggestion. Thanks for taking the time to post it.

RX-GR8

hmm so you think resetting the ECU had this affect?

eclps0

i think it does i have always used shell gas since day one same pump same gas station. Shifted teh same the same everything except the ecu being reseted.

RX-GR8

i gave up shifting at certain points. it has had little affect on my MPG. so i wind it up any chance i get. thats what this engine wants.

8_wannabe

eclps0, I shift about like you, maybe a couple hundred rpm higher. Maybe I'll try that unplug-the-battery trick. I consistently get 16.5 mpg no matter what I do or how I drive. How many tankfuls have you gone thru since pulling this trick? Did u change your driving habits?

eclps0

first tank 19.4 mpg
second tank 20.6mpg
Third tank dont know yet just filled up about an hour ago

RX-GR8

if i do mostly highway i can break 20 easily. how many miles on your 8 eclps0? has your city/highway driving changed?

eclps0

I drive alot in ft Lauderdale, la solas, and riverfront where its bumper to bumper traffic. I also drive on I 75-595 to get to school.

Charleston

I get about 21 MPG with 60/40 hiway/city. I routinely shift at 3500 RPM or lower going from one gear up to the next. On a trip from Las Vegas to San Diego I got 25.1 MPG but I never went over 70 MPH. The harder you accelerate the more gas you waste because Mazda is going to make your engine run fuel rich so you don't burn it up. To me it is just as much fun to reach 85 mph by sneaking up on it as flooring it to get there.

If you want to get to 85 mph fast then quit complaining about your MPG. If you don't mind taking a little while to get there--enjoy that sweet sound of the wind being louder than your engine:-)

markfw

Or you could drive like me. I shift at redline, and keep going until I hit the speed limit (usually second gear) then shift into 5th or 6th. Mileage sucks, but its fun getting there. (12-14 mpg)

MEGAREDS

Are people with ATs getting bad mileage? I've been getting a consistent 18-19 mpg.

eclps0

Charleston If u were talking to me this is directed to you if u weren’t talking to me than don’t read what is below.
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Ok if your reading this u directed your comments about me whining, well where in this post was I ever whining about the gas mileage? Ok so before u say something about me or assume how I acted or reacted towards my mpg. Know the facts!!!




P.s I posted my findings for people that were worried about mpg.

93rdcurrent

I know that I am averaging about 14-15 mpg now and when I first brought my baby home it was more like 9-10 mpg. She only had 7.5 miles on her that night and now she has 1600. I drive conservatively about 50% of the time. The best gas milage I have been able to acheive has been on the highway at about 19 mpg.

Has anyone had any success taking their car back to the dealer on this matter?

khoney

Y'all are making me cry! For those who shift below 4K, please consider selling your car to someone who can truly appreciate a rotary engine . Seriously, if you don't ever take your 8 into the upper RPM range, you aren't treating it nicely. My own motto: "A redline a day keeps the mechanic away" :D

Rotaries need to be driven - don't baby them for the sake of gas mileage. You'll regret it in the long run. Besides, it really shouldn't affect your mileage much at all. The mileage suffers mainly due to stop-and-go rush hour driving, when you're mostly at idle. Winding it up to 70MPH with a couple of redlines will not affect your mileage much at all - I do it at least twice a day, and I still get 18-20MPG.

shift_zoom8

Khoney, you might be right. I have babied my car for about 20 tankfuls, getting a high of 22.65 and a low of 18.68. My average is between 20.5 and 21.0. My lower mileage tanks seemed to happen whenever I got caught in traffic or city stop-and-go at any appreciable amounts (even a little bit of stop-and-go seems to pull the mileage down significantly).

I'm finally satisfied that I probably don't have a mileage lemon, so beginning with my current tank of gas, I'm testing if being more liberal with the gas pedal (lots of semi-hard acceleration, shifting at 5000-6000 rpm instead of 3000-4000 rpm) and average speed will have an appreciable effect. I don't want to speak too soon, but so far it looks like it won't pull the mileage down very much.

I'll report when I get results.

Greg

I may have the strangest habit of all. I wind 1st and second out and shift directly into 6th. I rarely ever use 4 or 5. I use 3rd alot but when I want to accelerate I just cant justify rowing through all those gears when just a couple will do. You are already at the legal limit after 2nd anyway. I get 18 mpg. average.

Elara

Greg, I do that a lot too, when I'm on roads that allow it. 2nd gets me up to cruising speed, and when I hit redline I just pop over to 6.

I was one of the ones getting really good gas mileage to begin with, and now my mileage is getting worse. why? Because I drive the hell out of the car now. As someone else said, I know I can get the mileage if I want it, so I'm just having fun now. The current tankful is looking the worst so far- I've got 90 miles on half a tank!! I usually get at LEAST 130 miles before it hits the halfway mark.

guy321

I don't know where Davie is.. but here in Clearwater it's been cooler than normal. Does air temp affect gas mileage?

KKMmaniac

Hey eclps0;

Have you noticed any difference in the car's performance? I was going to try this over the weekend, but thought "ehh, something so simple as disconnecting the battery for 12 hours couldn't possibly make a difference!"

Did you follow any specific procedure when driving the car afterward so the computer would "relearn" in a certain way?

cruzdreamer

My mpg has improved a little....From 12 mpg to 15.3mpg. The car has about 1400 miles on it now. I put midgrade gas in it. I am hoping it will get closer to 18 mog someday. How are the automatics gas mileage compared to the stick shift cars? Anyone with auto's out there with good or bad mpg?

pp13bnos

Well guys my milage is slowly coming up too. It use to be right around 13-14mpg, but has increased to 18mpg. I'm also driving the car alot harder, wich is kina odd. Best tank was a little over 25mpg. CJ

aussie77

Figured I would add my 2 cents in here. I have gotten perhaps the largest range of MPG of anyone on the boards now

As I posted in another thread, I had a 23+ mpg tank on a weekend spent doing almost 100% highway driving.

Well, since the weather turned cold here in Atlanta, my last tank of 100% city driving was beyond miserable. In stop and go traffic for most of the tank, I managed a paltry 168.1 miles on 13.29 gallons. If you run a quick calculation, that is less than 13 mpg! (12.65 to be exact). Now, I know my car isn't a lemon or I wouldn't be able to get great gas mileage on the highway when I need it.

Which means there has to be another explanation. I always knew that the stop and go driving in city would make the mileage worse, but I seriously believe that the weather has had a large effect too. Consider that over the exact same route a couple of months ago in warmer weather with a tank of 100% city, I got in the range of 16 mpg. That's a fairly large variation. The motto? Let your engine warm up, and avoid stop and go traffic!

jtimbck2

Just for the record, my original post wasn't about shifting at low RPMs, it was about using 4th gear where I'd use 3rd on a 5-speed. I generally do shift around 5000 rpm, and I redline it whenever I have the opportunity!