Filling up and accurate calculations for gas mileage.

SubCompactor

Member
:
mazda 2 touring
I am primarily driving in the city stop and go and had concerns with the computer and the computer average when it comes to mileage. I want to feel that 5-speed two can and does get 32mpg or darn close to in city when driven conservatively. I now believe that the computer is fairly accurate when fueling up (NOT "Actual" topping off) and getting the pump nozzle to stop after the first click. Some people go beyond that which of course is not recommended. I also know now to reset that computer average with each tank along with the tripometer.

So I wanted to know two things.

1.) Driving around town (conservatively w/o a/c on) should I expect to get 32mpg? (little to no highway)

2. Is the art of the fillup, consistantly? In other words, to use the same station same pump(s) and to stop fueling when the pumps clicks and shuts off the first time?

Thanks for the input!
 
I've never been below 32 mpg no matter where I've driven, so the answer is yes.
The only time I get in the low 30's (32-34) is with the winter-blend gas.
My fill-ups are done when the pump clicks off.
 
check out my fuelly in my signature...i run a 33mpg average, i've seen as high as 35mpg and as low as 30 when im really on the gas...but conservative driving will net you more than 32 mpg guaranteed on city streets
 
Shaowq, that is nice to hear. How do you perform your fillups? Same as MacAttack7 when the pump clicks off?
 
SubCompactor, does it really matter that much?

I mean, it does matter if you just calculate gas mileage over a single fill-up, but if you use something like Fuelly, it all averages out over time, even if you fill it up to somewhat different levels each time.
 
If you're just driving around in the city, I'd recommend always turning your TCS off. Smoother launches, smoother shifts, and it's suspected to be better on gas. I always go to the same shell station and get the same pump if at all possible (I won't wait for it, but if it's open I always go for it), and I always stop at the second click. So it clicks off, I squeeze it again until it clicks off again.

So to answer your question, yes, consistency is key. doesn't matter how you fill up, just do it the same every time. Like arcxer said, It all averages out over time.
 
I seem to get a consistent 30. My high is 34, low being 27. I am going to try and see if turning tcs off helps at all. Any other tips?
 
I don't drive a 2 so can't comment other than I'm often able to match and beat my EPA estimates. My computer is WAY more optimistic than reality ... often by 5mpg.

Keep in mind there is always going to be some variability depending on road conditions, temperature, traffic, etc., even on the same route. You will also get lower gas mileage in the winter if you drive in areas with winter gas formulas (by a couple mpgs for me).

I don't think the minor variances in fill will seriously effect your results.

Regarding whether or not you need to use the same gas, etc. depends on if you are going to monitor your mileage over the long haul, and want to keep certain variables constant so you can monitor other variables. To get the best mileage (and other reasons) I'd think you'd want to use the best gas possible. I always use Top Tier gas. www.toptiergas.com
 
I have a 2011 M2 Touring, with a manual trans and California smog equipment. I've installed a Racing Beat Muffler and an Injen Cold Air Intake. My round-trip commute to work is 160 miles every day. My average mpg is 36.7. I'm sure I could do better if I would drive 65 mph instead of 75 mph on the freeway.
 
If you're just driving around in the city, I'd recommend always turning your TCS off. Smoother launches, smoother shifts, and it's suspected to be better on gas.

I googled a bunch of threads regarding this & every single one said turning TCS off will not affect your MPG's at all.
So if that's the case, you should leave it on for safety reasons.
 
I googled a bunch of threads regarding this & every single one said turning TCS off will not affect your MPG's at all.
So if that's the case, you should leave it on for safety reasons.

You can google all day every day. Real world experience trumps google searches. I ran my first full tank with the TCS off. Smoother launches, better acceleration, 40.9mpg for the tank. I got over 430 miles out of my last tank. I understand what you're saying, but I disagree.
 
You can google all day every day. Real world experience trumps google searches. I ran my first full tank with the TCS off. Smoother launches, better acceleration, 40.9mpg for the tank. I got over 430 miles out of my last tank. I understand what you're saying, but I disagree.
I tried it for a week & didn't notice anything.

From what I read if it doesn't activate then it doesn't do anything, and I've very rarely seen my light come on to show it has activated.
Plus I don't really drive hard enough or on slick roads to ever activate it.

Any idea why you are getting the results you're getting? I don't know too much about the system, but I don't
understand why it would affect anything if it's not activating. It sounds like it's doing something on your car though.
 
Its geared more for 40-50mph to get the best mileage. Driving 55 can get you 40 mpg, driving a steady 45mph can get you 59mpg if youre lucky enough to have a 45mph with no stop lights and light traffic commute. I think that in easy city driving you will be 33ish or better, unless its true big city traffic. When you let off of the gas it cuts the fuel, so you dont have to shift to neutral when slowing down, but keeping it in gear will slow you down. Also another thing ive noticed is 5th gear isnt always the best gear to max your mileage, especially going up a slight hill and you find yourself mashing the gas more in 5th than you would in 4th....its a weak car, so being in the right power band will actually help you. I tend to think of how hard your mashing the gas as being more important of the gear when it comes to mpg's.

Thats the extent of my wisdom.
 
One week, as an experiment, I tried getting into 5th gear as soon as possible for the entire week & it did nothing at all for my mpg,, so now I just drive normal & shift when it sounds & feels right to shift.

After reading some mpg threads in the Accent forum & looking at Fuelly.com, in the real world, the mazda gets just-as-good, or maybe even better mpg's than the Accent even though the Accent has the magical 40 mpg hwy rating & the mazda is only rated at 35 mpg for some reason. If I drive hwy in my mazda I get 40 also, even got 45 once. That's just driving normal. I'm not sure why the mpg ratings are so strange for the manual trans mazda.

So all these cars that are rated at '40-Hwy' sound so much better on paper, but in the real world, you don't do all your driving on the highway, and the ratings on the manual Mazda are just plain wrong. I'd like to see all of the vehicles compared going about 40 miles per hour. I wonder if the Mazda would come out ahead then. (same with the Yaris as I've always read it's mpg's are pretty impressive also in the real world).
 
One other thing to keep in mind is tires, specifically tire pressure. I know a lot of guys that "hyper-mile" drive, and they over inflate their tires to get an easier roll. You can also get tires that are designed for better fuel mileage as well. With my cars/motorcycles, i can't drive without accelerating quickly, so maybe I don't know what I'm talking about... :-D
 
No BS here: I just completed a 1200 mile trip. Highway mostly. Above 70 MPH the car dropped to 34-36 MPG. At 45-55 MPH the car achieved 42 MPG. And this is with Yokohama Advan AD-08 (read high grip) in a 205-50-15 size (narrower tires get better MPG and some tires not designed for grip but for fuel economy trade grip for MPG. So, make up your own mind when it comes to what your goals are. FYI in agressive city driving in heavy traffic I dropped below 24 MPG. Still better than some muscle cars that I had where I achieved 1-5 MPG in same scenario. YMMV. But I think that the sweet spot for the M2 is suburban driving where top speeds stay below 55 MPH. A Corvette engine is barely working at 65 MPH so it is efficient and gets over 30 MPG at most freeway/highway speeds, where the M2 1.5 struggles a bit. Also the short body does not help in the aerodynamcs field. A longer sleeker body does much better.

Hope this helps in solving your quest for efficiency.
 
I just completed a 1300 mile (highway) trip and attempted some hypermiling on the last leg of it. I managed 36.5 mpg at my best before the hypermiling. The rest of the trip was low 30's doing 68-72mph. The tank with hypermiling managed a record amount of miles BUT the first half was furthest thing from hypermiling. Through the mountains of WV I got significantly worse mileage and the urge to put a turbo on this thing, as it didn't want to go up some of the mountain hills.......... the cruise refused to keep it at 70mph, it would drop to 65... even off the cruise it just would NOT go any faster using 5th gear lol.

I'm continuing the hypermiling through this tank just to see... will report back. I do city/back roads that are hilly/curvy/tiny bit of highway on my way to work.
 
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I just completed my second tank with the TCS turned off full-time. I averaged 41.4 mpg and 377.6 miles on the tank. It took 9.114 gallons to fill it. I don't know if what I do is considered "hypermiling." I definitely keep my stock tires at about 37psi (which is higher than suggested, but not crazy). I do a lot of anticipating. I do a lot of the same drives throughout the week, so I have pretty good feel for when to let it coast up to a traffic signal (for instance, with a light that will almost certainly turn red before I get to the intersection, instead of hammering on the gas and try to make it, I just resolve to let it coast and take the red). I'm not drafting semis or turning my car off on downhills though.
 
Above 70 MPH the car dropped to 34-36 MPG. At 45-55 MPH the car achieved 42 MPG.

This mirrors my experiences as well. I haven't gone faster than 60mph at all this week (filled the tank on Saturday), with the vast majority of my commute at 55mph. The trip computer (reset when I filled the tank) is showing 43mpg right now; I know it's a little high, so I'm expecting to end up with a real-world 41 mpg the next time I fill up.

I averaged 35-36mpg when I did a road trip last summer and did 65-70mph the whole way. Tire pressures, then and now, are at 38psi.
 

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