18.5 mpg?

[Hix]

Originally Posted by Dadhawk

As noted in my Owner's Journal (see sig. for link) I use mine almost exclusively for commuting in Atlanta traffic.

That's about 40 miles one way in Atlanta traffic, usually 4 days a week. About 15 miles of it is "city driving" with speeds under 45, and stop and go traffic. The rest is highway speeds, but varies from 70MPH to stop and go depending on the day, and can include significant "idling time". It also includes "city driving" doing normal day-to-day stuff around my home, all between 35 and 55MPH with lots of stop lights, etc. Based on average length of time, I would say speed wise I average about 42MPH in the mornings and 35MPH in the evenings.

I make no attempts to improve MPGs and drive somewhere between safe and aggressive. I usually drive in full auto, but make a lot of use of the paddles for downshifting (its pretty much second nature now, I don't even consciously do it)

After almost 7K miles of this, I'm averaging just shy 32MPG with the 6AT. Absolute worse was over 29, best was over 34 (which was a road trip not a commute).

I don't know how you do it. I am like the OP and stuck in the sub 20 area driving an auto and being very very very very very very gentle. I even started turning the car off in traffic. To put it in perspective on the weekends it takes 10-15mins to drive to work if I drive carefully and go the speed limit and all that jazz. However, during the week my normal morning commute is around 1.5-2 hours to go the same distance. The main reason for this is that in that 7 mile stretch between the house and work I pass 8 schools. Going the other direction I will pass only 5 schools but two of those are private and have traffic guards giving their students the right of way. I think I might go back to riding my bike to work and just take my chances on the highway crossing. My absolute best was when I spent half the tank driving during the day to downtown which was around 25mpg with pure highway driving.

[Dadhawk]

Originally Posted by Hix

I don't know how you do it....

I think I'm just numb to it at this point. I've always somehow managed to live as far away from work as is reasonably possible. Never started out that way but I'll change jobs and boom, right back at it.

Longest commute I've had is when I lived in Florida. Almost 60 miles, but it was a straight shot on an uncrowded highway, rarely took more than an hour. When my first son was born I made it in a little less than 36 minutes because my wife called and was in labor with no way to get to the hospital. Thankfully the road was so lightly traveled there were never any troopers on it.

If it took me 2 hours to go 7 miles, I might have to give in and just walk! Ouch. I'm sure if my average speed matched yours, my average MPG would as well.

[Rob_g]

I think the fuel can affect mileage as well. I was using shell v-power 91 (no ethanol), but noticed my fuel economy was getting worse by at least 0.7L/100KM. I tried driving easier and it did not get better. I switched back to co-cop 91 gas which probably has %10 ethanol and the mileage got better even with me driving it harder. This is city driving and I have an auto tranny by the way.

But I think the way the car runs real crappy sometimes is also having an effect.

Rob

[zoomzoomers]

I think I figured it out. Previously I've been reseting my avg mpg clock each time at fill up. Then I'd do my normal 95% grid lock city driving every day. I've since driven on the hwy some and have not reset the avg clock. Now I'm holding steady at around 24 mpg driving the way I do. I guess I've been seeing the low avg numbers because I was reseting the avg clock every time I filled up. Now I'm just reseting the total miles clock at fill ups and leaving the avg clock alone. So I'm getting an "overall" average mpg. :happy0180:

[gmookher]

24 mpg with tunes
27 mpg with stock tunes

[BoxeRZ]

Just hit 2K after 1 month of ownership. Dash is telling me ave. 23.5mpg. I dont actually do the math because I would have bought a hybrid if thats what I cared about. Although, I am a bit surprised by such low MPG in a 4 banger. My round trip for work is a woping 5 miles, then after work I drive very spiritedly for at least an hour on the beautiful back country roads of PA.

[goke186]

I'm almost wondering if your second set of injectors arent shutting off after initial warm-up/start

[jeebus]

I've averaged 28.5 over 3k miles. I drive the car plenty hard, a lot. I drive mixed city/hwy/canyon. My worst tank was 23mpg, that had 15 miles of autoX runs and a number of canyon runs.

Something is wrong with your car.

[RAWR BRZ]

I had too much fun when I first got the car... I did 5 spirited canyon drives and i reset mine at 100-200mi and it is slowly rising from 24.5mpg.

Keep it at 6th gear all the time... this is my shift points..

1st-2nd = 12-15mph
2nd-3rd = 20-25mph
3rd-4th = 30-35mph
4th-5th = 36-38mph
5th-6th = 39-40mph

Don't give it too much gas when driving like this or your whole car will vibrate and its bad for the engine... I drive real damn slow... to save gas lol... its 4.55 all the sudden... was like 4.33 last week...

If I am merging onto highway I move everything up by 10-15mph I think... Basically I am going 65mph before I merge.

Btw how many gallons per tank are you guys getting?

[jeebus]

you don't smell gas do you? I have a hard time believing this car would run properly while getting 18mpg in normal driving. that would be really rich, the car should be bogging in many areas of the powerband. I'd also assume your exhaust tips would look pretty gross.

Maybe you have a leak?

[DSPographer]

Originally Posted by RAWR BRZ

I had too much fun when I first got the car... I did 5 spirited canyon drives and i reset mine at 100-200mi and it is slowly rising from 24.5mpg.

Keep it at 6th gear all the time... this is my shift points..

1st-2nd = 12-15mph
2nd-3rd = 20-25mph
3rd-4th = 30-35mph
4th-5th = 36-38mph
5th-6th = 39-40mph

Don't give it too much gas when driving like this or your whole car will vibrate and its bad for the engine... I drive real damn slow... to save gas lol... its 4.55 all the sudden... was like 4.33 last week...

If I am merging onto highway I move everything up by 10-15mph I think... Basically I am going 65mph before I merge.

Btw how many gallons per tank are you guys getting?

You don't need to drive the BRZ like this to get good gas mileage. In fact the engine is most efficient at wide open throttle, so shifting so the RPM stays above 2000- so you can open the throttle without excessive vibration- is more efficient than a partial throttle start.
What kills gas mileage is:

Braking: using either the brakes or the engine at any gear below 6th to slow down just burns away kinetic energy. For good MPG, anticipate corners and stops to slow down gradually without much braking.

High RPM: Revving the engine above 3500 RPM really starts to impact efficiency. Open throttle starts that don't go above 3500 RPM are OK for efficiency.

High Speeds: Wind losses increase by the square of the speed, so high speeds are inefficient. Going so fast the engine is above 3500 RPM in 6th is especially inefficient.

Cold engine: Short trips result in burning a good deal of extra gas just warming up the engine.

Idling or going very slowly: Besides causing the need to use your brakes, city driving also has you running the engine while not really moving- which is obviously wasteful.


Spirited driving usually means more braking and higher RPMs- so the MPG goes down. But, if you tone it down just a bit so you don't need hard braking or too much time at redline RPM, you can get good mileage on twisty back roads.

If I drive the BRZ avoiding the above for best mileage, and don't get stuck in city traffic, I get >36 MPG.

I never do that for an entire tank though- it's too boring. So I usually end up getting about 32 MPG.

[Blake]

My latest avg mpg is 30. However it is usually around 27.

[arucard77]

I'm seeing an average of 24. 30/70 mix. I personally think that's low. I have been very kind to this car (for the most part, gotta have fun every once and a while).

My prelude was getting better than that. The Lude had the H22A motor with cold air intake dc headers apexi cat back sport clutch, took a lot of weight out of it, back seats, spare tire, a/c yadda yadda, and was getting 25-27mpg. And I drove that car like I stole it.

I am currently waiting for my B/O HPFP to ship, and recently have started having the idle dip...only a matter of time before that damn little light comes on. So wondering if this is the problem with the mpg's???

[chrisbfrs]

Originally Posted by dvlnsyde

WOW! I am getting 29-30 and my driving is 60/40 = hwy/city.

I was averaging 29.7 stock and now 29.9 with TRD air filter. I drive mostly city too,,,,,20/80 hwy/city
:happy0180: