Improving MPG Trend

[kwagar]

This is simply a report of my experience.
I have owned my smart since Feb 1, 2008. I currently have 10013 miles on it. I live in Central Florida.
I have tracked each tank of gas and my resulting MPG since Buying the car.

I drive the car like I have driven every car I've owned. I do not hyper-mile or drive to achieve any MPG records. Since picking up the car my mileage in total has averaged just under 40 MPG and I have been very happy with that result.

I do not get very excited about my MPG for any given tank of gas. I think the only accurate way to guage MPG is over multiple tanks and longer periods of time.

What I want to report here is that for the first time I have achieved in excess of 40 MPG for 7 consecutive fill-ups covering 1300 miles of driving. This is clearly a trend when one examines all 37 of my fill-ups. My mileage record can be seen below.

There are only two things that have clearly changed during the time of these increases. 1. The trend started at the same time I added nitrogen to the tires. I will tell you I was very skeptical obout any benefit of Nitrogen and only filled with it because I was able to do it at no cost.
The second change was my 2.0 upgrade early in this trend.

I would not try to make the case that these changes resulted in the mileage gain I simply offer the data so that you can make your own decision.

The roads, the weather, the speeds and my driving style have had no appreciable change during this time. My average mileage prior to these 7 tanks and 1300 miles was about 39.5 MPG the last 7 tanks have averaged 42.6 MPG a gain of 3.1 or an 8% gain.

Again I offer this information simply as an FYI for those interested in MPGs


Fill # Miles Gals MPG
1 255 6.8 37.5
2 234.2 6 39.0
3 253.1 6.7 37.8
4 227.6 5.8 39.2
5 220 5.6 39.3
6 304 7.7 39.5
7 301 7.2 41.8
8 269.3 7.2 37.4
9 250 6.5 38.5
10 253.5 7.2 35.2
11 363.5 8.3 43.8
12 110.6 2.4 46.1
13 271.9 7.5 36.3
14 236.3 6.3 37.5
15 291 7.7 37.8
16 315 7.8 40.4
17 312.4 8 39.1
18 323 8.5 38.0
19 252 6.1 41.3
20 239.4 6 39.9
21 279 7.4 37.7
22 328.7 8.4 39.1
23 242.5 6.4 37.9
24 271.3 6.9 39.3
25 276 7 39.4
26 255 6.7 38.1
27 291 6.7 43.4
28 268 6.8 39.4
29 274 5.9 46.4
30 281 7.3 38.5
31 276.4 6.78 40.8
32 239 5.7 41.9
33 312.6 7.1 44.0
34 266 6.4 41.6
35 298 7.3 40.8
36 229 5 45.8
37 339 7.7 44.0

[aslusers]

Only four trips (#8, 21, 24, & 25) are based on 95% highway. As for the rest of trips are 90% city & 10% highway. As for the last two tanks are based on 2.0 upgraded version. We both rotates our driving on daily basis (Mostly, we fight over who can drive this car every day. Sometimes, we flip coin to see who get to drive that car that day. GRIN.)



Date Odometer Miles Gallons Cost MPG
1 May 7, 2008 245.5 245.5 7.255 $27.78 33.8
2 May 11, 2008 489 243.5 6.751 $27.40 36.1
3 May 19, 2008 783 294 7.42 $30.12 39.6
4 May 28, 2008 1069 286 7.448 $30.90 38.4
5 Jun 7, 2008 1347 278 7.842 $32.92 35.5
6 Jun 15, 2008 1621 274 8.157 $35.88 33.6
7 Jun 21, 2008 1809 188 4.874 $20.86 38.6
8 Jun 22, 2008 2054 245 5.45 $23.32 45.0
9 Jun 27, 2008 2334 280 7.017 $30.59 39.9
10 July 8,2008 2638 304 7.791 $34.27 39.0
11 Jul 19, 2008 2961 323 8.633 $37.72 37.4
12 Jul 30, 2008 3245 284 7.424 $30.13 38.3
13 Aug 7, 2008 3504 259 8.022 $32.56 32.3
14 Aug 18, 2008 3808 304 7.708 $30.05 39.4
15 Aug 29, 2008 4083 275 7.893 $31.09 34.8
16 Sep 13, 2008 4305 222 6.029 $24.95 36.8
17 Sep 24, 2008 4596 291 7.896 $31.58 36.9
18 Oct 9, 2008 4901 305 7.784 $25.99 39.2
19 Oct 22, 2008 5220 319 7.754 $21.78 41.1
20 Nov 5, 2008 5514 294 8.249 $18.06 35.6
21 Nov 7, 2008 5775 261 5.836 $12.60 44.7
22 Nov 17, 2008 6069 294 8.045 $16.48 36.5
23 Nov 21, 2008 6169 100 2.426 $4.80 41.2
24 Nov 22, 2008 6466 297 6.929 $20.50 42.9
25 Nov 23, 2008 6651 185 4.216 $8.13 43.9
26 Dec 2, 2008 6939 288 7.598 $14.57 37.9
27 Dec 13, 2008 7207 268 7.852 $15.07 34.1
28 Dec 30, 2008 7515 308 8.207 $15.01 37.5
29 Jan 10, 2009 7845 330 8.354 $18.37 39.5
30 Jan 20, 2009 8139 294 8.443 $18.40 34.8
31 Jan 29, 2009 8376 237 6.168 $11.16 38.4
32 Feb 8, 2009 8643 267 7.395 $14.56 36.1
33 Feb 20, 2009 8922 279 7.414 $15.56 37.6
34 Mar 5, 2009 9212 290 8.034 $15.82 36.1
35 Mar 15, 2009 9516 304 7.097 $14.33 42.8
36 Mar 23, 2009 9816 300 7.17 $15.55 41.8
37 Mar 31, 2009 10117 301 7.121 $16.02 42.3
38 Apr 10, 2009 10411 294 8.318 $18.79 35.3
39 Apr 22, 2009 10696 285 6.813 $15.66 41.8

[Woody14619]

Keep in mind, some of that may be that we're moving back to summer blended fuel as well. And if you swapped off snow tires back to all seasons or summer tires, that will impact mpg as well!

My last few tanks have seen a boost, but part of that has been a couple longer trips.

[Old smart]

It wouldn't add anything if I recited the numbers because my driving style, use and environment won't be the same as others. At delivery, the MPG was unimpressive and actually well below EPA estimates. As my careful but aggressive break-in period progressed, every fill-up showed an improvement over the previous one, though at a steadily decreasing rate. By two months and 1,500 miles later the increases pretty much disappeared, but by then I was overall 11% better than EPA, and I stopped calculating. Not long ago I again calculated a couple of fill-ups (+/- 6,000 miles) and I got just slightly better than at 1,500. I'm sure that the attentive break-in accounted for the initial increases.

[Gargoyle]

Originally Posted by Woody14619

Keep in mind, some of that may be that we're moving back to summer blended fuel as well. And if you swapped off snow tires back to all seasons or summer tires, that will impact mpg as well!

He said he is in Florida. While I am not sure if they change fuel blends, I would be willing to bet he didn't have to change to snow tires

[kwagar]

Originally Posted by Gargoyle

He said he is in Florida. While I am not sure if they change fuel blends, I would be willing to bet he didn't have to change to snow tires

That is correct. In addition I used AC very little during this time but also used it very little in the 3 months previous to this upward trend.

I make no claims as to the actual reason for the increase, I just find it interesting that it has taken place and has been pretty consistant. I supect that now that our summer heat is coming on (It was 89 degrees yesterday) I will see some drop off due to AC use.

[unicycle]

Originally Posted by kwagar

Actually, I think your trend started earlier. At fill 27, you began averaging over 40. The 46 and 38 of fills 29 and 30 are likely due to a too-fast shut off for one of those tanks. The same recently happened to me (I went from 53 to 42 to 52).

Fill # Miles Gals MPG
27 291 6.7 43.4
28 268 6.8 39.4
29 274 5.9 46.4
30 281 7.3 38.5
31 276.4 6.78 40.8
32 239 5.7 41.9
33 312.6 7.1 44.0
34 266 6.4 41.6
35 298 7.3 40.8
36 229 5 45.8
37 339 7.7 44.0

[Jordon]

Originally Posted by kwagar

I drive the car like I have driven every car I've owned. I do not hyper-mile or drive to achieve any MPG records.

Thanks you, got stuck behind someone the other day that doing this in his Yaris. Would accelerate really slow, start to slow down a mile in advance and never once hit the 35mph speed limit. Heck, I don't think he made it past 20mph. One lane road for like 10 miles, passing unavailible due to traffic.

Anyway, mileage is looking good. Summer fuel mixtures should be comming out so hopefully we start seeing some numbers in the upper 30's.

[unicycle]

Originally Posted by Jordon

Thanks you, got stuck behind someone the other day that doing this in his Yaris. Would accelerate really slow, start to slow down a mile in advance and never once hit the 35mph speed limit. Heck, I don't think he made it past 20mph. One lane road for like 10 miles, passing unavailible due to traffic.

That's not hypermiling -- that's being an A$$hole.

I'm a hypermiler, and for one thing, there is the zen of it. If you're making other people drive inefficiently, then you're not doing anyone a favor. In fact, driving below 35 mph is inefficient anyway -- 40-50 is much more effective.

And if I'm ever on a long 1-way road, I always pull over to the side to allow others to pass.

Is bumping someone illegal Seems like it might send the right message. Just a gentle tap.

[Bill Marshall]

Kawagar, my experience over 6400 miles has been identical to yours - incuding the change to nitro in my tires.

First 1000 miles = 35 mpg (winter)
Next 2000 miles = 38-39 mpg (winter)
Last 3400 miles = 41-42 mpg (spring)