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4carbcorvair
12-29-2012, 09:21 AM
Wifey has been getting 35-36 mpg in city driving, stop and go. We decided to take the car on a 440ish mile round trip to northern Maine recently. Speed limits of 65 and 75 north of Bangor Maine. We were only getting 30 mpg. Is this normal at highway speeds? Rpm's were ober 3,000 at 75. We now have aproximately 2,200 miles on the 500. I was expecting higher mpg, not lower. :/

William M Jacocks Jr
12-29-2012, 10:16 AM
To me, the magic number for speed/efficiency is 62 (+/-) As you approach that speed you can see the efficiency improve, but as you go over 62 to where you are actually pushing air more the efficiency drops. Seems close to what I am getting with my Abarth. My wife's new C-Max hybrid is doing the same thing.

SeaDawg
12-29-2012, 11:36 AM
No, that's not normal, at least for a 5 spd manual. With a 5 spd manual you should be able to get 37-40 at 75 with the A/C on. Even if it's an automatic, you should be able to get better than 30 on the open road. Now if the terrain was really hilly or there was a lot of wind then that mpg would not be uncommon, at least in the automatic.

madbyrd
12-29-2012, 11:41 AM
I now have nearly 18000 mi on my 2012 automatic 500 Pop, most of the time in my daily commute of 40 miles each way I drive conservatively and average 39 mpg. I have gotten as high as 43 but that is with the cruise set at 55 and mostly flat land. I select routes with fewest stops, coast or down shift to stops and try to guage my speed when approaching lights to prevent full stop/start. In my typical around town driving I get about 30-32. So overall I beat the rated of 28 city and 34 hwy. However, weekends are my fun times usually kicking in Sport-mode and shifting which drops mileage to about the 35 range. I usually fill with 89 or 91 octane.

4carbcorvair
12-29-2012, 12:53 PM
Thanks! It is a 5sp.

Roads are hilly, not much for flat land around here, and it was windy. Wife, our two sons and I in the car with a travel bag. Wifey and I are about 5'5" and not overweight....

Fiat500USA
12-29-2012, 03:23 PM
Hills and mountains make a huge difference. I live on a mountain and you can just watch the mpg plummet when the road starts climbing. The easiest way to get the best fuel economy is to use the cruise control on the highway. However, if you have a rock steady foot and can maintain the same position for long periods of time, you may get more mpg if you want to work at it, especially if you watch the instantaneous mpg readings and ease off slightly when the mpg go down. Also let your speed bleed off going up hills. This may bother people following you, though. You've been warned! LOL

Another way to improve fuel efficiency is to use the ecoDrive system. This will give you important tips on getting the best fuel efficiency. One of the secrets in getting the best mpg is to shift early - 1700 to 2100 rpm. Any higher and your fuel economy will fall off. This is, by the way, a good practice to improve the economy on most cars. Note the Abarth likes a little more rpm for the best economy due to boost and fuel enrichment.

Also, don't forget to turn off the Sport button. Using the Sport button will not help fuel efficiency.

I make getting better gas mileage a challenge. For me, it is a fun way to interact with the car not have to worry about getting tickets and attracting the police. I'm trying to decrease that interaction. angelgrin

Robert Nixon
12-29-2012, 08:05 PM
Getting around 30mpg with passengers in hilly windy conditions may not be too bad, but it does sound on the low side. My Abarth was around 34-35mpg on about 120 freeway miles today, just two adult passengers, not very hilly, not windy.

500
01-03-2013, 12:40 AM
To me, the magic number for speed/efficiency is 62 (+/-) As you approach that speed you can see the efficiency improve, but as you go over 62 to where you are actually pushing air more the efficiency drops. Seems close to what I am getting with my Abarth. My wife's new C-Max hybrid is doing the same thing.

This exactly. I did some playing with the car this week both in the city and on the freeway, and I think that 58-62mph are the most efficient. Things definitely drop off above that, but not so profoundly that 30mpg should be your average. You might start with looking at your tire pressures, then consider your driving/acceleration habits. If you're not also using 91+ octane fuel, you might try that as well. I've been averaging 47ish mpg in the city right now, and mixing freeway in allowed my into the 48mpg range, not the other way around.

-- Julie

panther76
01-03-2013, 04:17 PM
Wifey has been getting 35-36 mpg in city driving, stop and go. We decided to take the car on a 440ish mile round trip to northern Maine recently. Speed limits of 65 and 75 north of Bangor Maine. We were only getting 30 mpg. Is this normal at highway speeds? Rpm's were ober 3,000 at 75. We now have aproximately 2,200 miles on the 500. I was expecting higher mpg, not lower. :/

also, it may be that your "city" driving may be closer to what many of us would call suburban type driving, which can in some cases provide more optimal conditions for mpg's than interstate driving.

on the other hand, others here have city driving that is really stop, sit, sit, sit, go, stop, sit, sit, go...etc, etc...guys in LA, NYC, Chicago, Mexico City....where

luckymoi
01-03-2013, 06:39 PM
In top gear (cabrio, automatic) going along Santa Teresa Blvd at 42 mph, instant read out is in the 50's...
53.2... 59.1... That with a frozen right foot; using cruise control its slightly less.
When the stop light is red, its a sad tale...
This car is very entertaining!

4carbcorvair
08-26-2013, 05:38 PM
Now with over 10,000 miles on the Sport, I get between 40.2 and 40.5mpg's with our usual driving. Highway has gone up to just over 38, with speeds posted at 75.

dart1.4t
08-28-2013, 06:44 PM
ehh. gas mileage is complicated.... engines turn fuel into power most efficiently at torque peak under full load but there is a power enrichment mode that can mess things up. the tricky thing about that is the car is drive by wire throttle and i don't know what triggers power enrichment. traditionally it's when the throttle blade hits a certain % opening which can be from 75-90% but on drive by wire it might be at an indicated torque value or intake pressure for that rpm so it can be a hard to predict curve. but of coarse it's not as simple as driving at torque all the time. the reason that fact is true to begin with is that torque peak indicates the highest "BMEP" or break mean effective pressure, a fancy way to say the average pressure in the cylinder is highest and high cylinder pressure has a correlation with low fuel consumption per hp/hr. but if you don't need much torque to move the car you will have high manifold vacuum and low bmep so low rpm and a high gear is better. the high efficiency at torque peak also mean it it the most efficient way to get up to speed and get up hills. that works going up hills but even though you reach x mph with less fuel at torque peak you also cover less distance because you are accelerating hard. so with lower fuel used the distence is also lower, os which is better? the hypermilers say everything should be smooth and gradual but there have been articles that say 75% throttle untill you reach speed is best. who knows. i tend to hit the gas hard and shift under 3500rpm. i also get consistent 38mpg fillups in a dart, mostly highway but with hills and i can get the gauge up to 46 or better locally if nobody gets in the way and my gauge tends to be very conservative like 10% less than the hand calculated values.

the reason highway tends to be better is you don't stop. it does take more energy to go faster but you get to preserve the momentum. if you can get a decent distance before stops locally you can sometimes do better.

Indie500L
08-29-2013, 08:26 PM
Tire pressure is also a very big factor - get the pressure up to about 40psi COLD and you will see a big difference from 32psi - plus road surface can affect rolling resistance - some of those northern states have more grip for snow and ice conditions. I once saw a big change in mileage just crossing from New Hampshire into Mass on the same road along with a change in tire noise - the mileage increased in Mass.

CASD
08-31-2013, 01:47 PM
Last tank 27.7 mpg in town avg. MPH 17 2013 Pop 500 Auto .. Haven't taken on any trips yet so can't give MPG for freeway...
mileage is not biggy...
Look at these facts..
Toyota Prius $27000
My Pop $15000
Avg 12,000 miles a year,,
$3.70 per gal..
Prius savings...$600 per year..
It would take 18 years to make up the difference in prices..