[russell_314]

I have a 2014 smart fortwo 451 with a 1L gasoline engine with just over 61k miles. It seems to run good but I never owned a smart before to compare it to. I'm looking for tips or maybe something I'm missing to improve MPG. I get between 33 and 36 MPG. My driving is probably 3/4th highway at 65-70 MPH. Most of the time I leave the shifting to the car. I don't push hard on accelerations because I figure that might not be good but also don't try to drive crazy slow like grandma. I keep it within the speed limit. Most cars will pass me when the light turns green and I usually stay in the right lane unless turning left. I hear people talk about 40+ MPG so I was hopeful there is something I could do.


I'm using Mobile 1 0W-40 European Car Formula oil. I change it and the filter every 5k to 6k miles.
The transmission fluid was changed at about 45k miles with Amsoil 75W-90 API GL4 manual transmission gear lube.
The engine air filter was changed when I got it at about 45k miles and just now at 61k miles. It wasn't really dirty the second time around. It's the standard $20 paper air filter from O'reilly auto parts. I thought about getting a K&N but worry about dust getting through.
The spark plugs were changed at about 50k miles but the old ones looked almost new and it didn't have any effect on MPG or how the car ran.
All four tires have been replaced with the exact factory Continentals at about 50k miles. 30 PSI on the front and 34 PSI in the rear is what I keep them at.
I use premium 93 octane gasoline but unfortunately where I'm at it's 10% ethanol.
Most driving is with the windows up on the highway and lately down in the city because it's been cooler. In the summer I kept the AC on because it was in the 100s but since it's been cooler I haven't used it nearly as much and haven't noticed a change in MPG

 

[jwight]

Looks like you have the car in good shape. Using the A/C does hurt the mpg, but there are so many variables in how and where we drive it's hard to single out one thing that may be dragging the mpg down. PS - the 451 engine has a 6K redline and it doesn't hurt to put your foot in it occasionally....

 

[smartiealbert]

I run 40psi in all 4 tires, and don't use the AC unless bogged down in traffic. Burn 93octane, run 5mph over
whatever posted speed limit. Live in mountains, everything up/down hill. Winter blend gas= average 38MPG
and with summer blend= 40/41MPG. 2013 passion with 41,000 miles. FUELLY.com lists owner reported MPG for all makes/models cars.......................

 

[Shalmaneser64]

I get low to mid 30's typically on my 2015 Pure. I'm running larger 185/65R15 / 205/60R!5 tires. I have the air intake tube mod and a K&N filter, and a side air scoop. I have noticed a tendency to get an increase in mileage recently with the cooler weather. It's kissed 40 MPG based on the trip computer, if I don't drive it like it's being stolen. I seldom leave it in automatic anymore. Easier to just rev it and shift it where I'm comfortable with it - 5,000 - 5,500 RPM. It's not a rocket, but it's not a slug either. It'll move if you punch it.

 

[gtdump]

Your driving habits have a significant impact on MPG. I've heard a lot of folks say that scangauge/ultragauge/etc are handy for finding the sweet spots. I get 36-42mpg with my 2008, but I'm usually rural driving at 50-60mph.

 

[MB DNA]

smart is “right sized” by design and while 33 - 36 MPG is a tad low, without driving w/a raw egg on the gas pedal shouldn’t expect much more.

With smart’s diminutive size it looks like it should get a BAZILLION MPG?

With the aerodynamics of a brick, headwinds and elevation changes 50ish is my observed high.

But then I “drive like I stole it” grinning from ear to ear!!!

 

[smark]

I achieved 43 mpg once using 93 octane fuel. Straight run on the highway. Nice sunny day.
I average 34-38 mpg city and highway driving. Some people Exaggerate their fuel economy.

Driving a smart, it sounds like your getting the normal fuel economy.

 

[OliverB]

My experience with both a 451 and my current 453 is that the 451 got slightly lower gas mileage at Interstate speed. Having one less gear increases rpm at speed. Also depends on terrain in your area. Hilly will result in less mpg. Use of AC in the summer will lower mpg. The compressor robs a good bit of power on hot days. I did see mpg lower than 40 in the summer.

 

[Jo e Lefors]

View attachment 64645
I achieved 43 mpg once using 93 octane fuel. Straight run on the highway. Nice sunny day.
I average 34-38 mpg city and highway driving. Some people Exaggerate their fuel economy.

Driving a smart, it sounds like your getting the normal fuel economy.

Russell 314
Sounds like you're driving your smart like a normal person would drive and you're getting mileage right in the middle of the EPA est.
My mpg is right in the middle of the EPA estimates at a rock solid 36 mpg. Mix of 70% hwy 30% city and 100% paddle shifting right around 3000 -3500 rpm, top down, no a/c.

 

[Miss Mercedes]

I have a 2008 and a 2012 451. The 2008 averages about 38 while the 2012 averages about 42.

I do employ a few hypermiler tactics on the highway like drafting trucks (which also means I don't have to downshift on hills). My best trip to date was 58 mpg for 500 miles. The catch? I was going 30-60 mph directly behind a school bus camper the entire way. We used to have a guy called "Unicycle" on here that was the undisputed champion of getting the engine to sip the least amount of fuel. There was another guy that got 60 mpg too, but he never exceeded 50 mph and basically always lugged the engine no matter what.

The 2012 used to average 45-48 as I used to be more aggressive at saving fuel. But nowadays even I like to bang it off the rev limiter. I average maybe 33 mpg around town nowadays.

The 450 and 453 I have are different animals. The 450 regularly hits 50 mpg with me behind the wheel and the 453 never gets over 42 mpg. Granted, that turbo's addictive so I'm always racing the little thing.

 

[smark]

Folks getting 40-50-60 mpg’ s are probably sampling instant milage, not average mpg. There is a big Difference. You figure, tank to tank Fill up.

 

[gtdump]

Folks getting 40-50-60 mpg’ s are probably sampling instant milage, not average mpg. There is a big Difference. You figure, tank to tank Fill up.

I keep records of every tank starting the day I bought it nearly a year ago.
Average over all miles divided by all gallons is 39.52MPG

I've had a number of tanks over and under 40mpg, depending on my lead foot, weather, etc. Always premium and usually the posted speed limit +5mph (actual, not speedo) so usually 50-60MPH with the occasional sprint of 70+ (never over 90(speedo) due to the limiter) . I can see someone getting 45+ with a bit more effort, fewer stops, or fewer curvy roads; over 50 I get skeptical.

I also recorded the 13 years and 175k miles I put on my SL1. It averaged only a little less, 36MPG and was still getting that when it drove off this summer with someone else. Kinda wish I had kept it and fixed it instead, but space limits....

 

[Miss Mercedes]

Folks getting 40-50-60 mpg’ s are probably sampling instant milage, not average mpg. There is a big Difference. You figure, tank to tank Fill up.

Nope! Lifetime fuel economy! You can easily cheat fuel economy by driving slow (like mrbadexample did) or by drafting huge vehicles (like Unicycle and I did/do). The hard way (the way Chumly did it) would be to improve the car's aero. There are many ways to beat fuel economy ratings without cheating by taking instant snapshots.

That said, under normal driving conditions you should be mid-ish 30s. ¯\(ツ)/¯

 

[Audi2Smart]

I have a 2014 smart fortwo 451 with a 1L gasoline engine with just over 61k miles. It seems to run good but I never owned a smart before to compare it to. I'm looking for tips or maybe something I'm missing to improve MPG. I get between 33 and 36 MPG. My driving is probably 3/4th highway at 65-70 MPH. Most of the time I leave the shifting to the car. I don't push hard on accelerations because I figure that might not be good but also don't try to drive crazy slow like grandma. I keep it within the speed limit. Most cars will pass me when the light turns green and I usually stay in the right lane unless turning left. I hear people talk about 40+ MPG so I was hopeful there is something I could do.


I'm using Mobile 1 0W-40 European Car Formula oil. I change it and the filter every 5k to 6k miles.
The transmission fluid was changed at about 45k miles with Amsoil 75W-90 API GL4 manual transmission gear lube.
The engine air filter was changed when I got it at about 45k miles and just now at 61k miles. It wasn't really dirty the second time around. It's the standard $20 paper air filter from O'reilly auto parts. I thought about getting a K&N but worry about dust getting through.
The spark plugs were changed at about 50k miles but the old ones looked almost new and it didn't have any effect on MPG or how the car ran.
All four tires have been replaced with the exact factory Continentals at about 50k miles. 30 PSI on the front and 34 PSI in the rear is what I keep them at.
I use premium 93 octane gasoline but unfortunately where I'm at it's 10% ethanol.
Most driving is with the windows up on the highway and lately down in the city because it's been cooler. In the summer I kept the AC on because it was in the 100s but since it's been cooler I haven't used it nearly as much and haven't noticed a change in MPG

As JWRIGHT noted and I concur, the AC makes a huge difference for me. If I travel highway on a cool to mild day with cruise control on I easily get 50 MPG. 2017 model here.

 

[wmf2008]

a/c probably makes about a 3-5mpg difference for me. usually get 30 - 36 locally, tried no a/c on the highway last week and got 43...

go figure

Bill

 

[Jersey Smart]

I own a 2013 pure. Don’t drive it much at all however I’d say I have driven it pretty easy when figuring fuel economy. Mine does not do well either. 32-34 mpg. Mostly highway driving. I have since installed the day star lift with larger tires however have not really driven it at all to check the mileage.

 

[mike5511]

40ish, plus or minus a few. However, drove from South Tahoe to Yosemite and back, 380 miles, and it held 5 gallons! First thought was I figured wrong. But I didn't. Motorcycle mileage use to go up too when we rode at higher altitudes. Never got 76 MPG with the ol' hog though!

 

[russell_314]

Thanks for all the replies. Sorry it took so long to get back but I’ve been busy with vacation. I have ScanGuage II but I’ve never messed with the fuel economy part. I bought it for the coolant temp and voltage gauges. After frying the clutch on my first car because the idiot light for temperature came on too late I can’t stand not having proper gauges. I ordered a silicone hose and high flow air filter. I was a bit reluctant but hopefully it filters enough.

 

[mike5511]

............ I thought about getting a K&N but worry about dust getting through.

Wise choice. I've got a friend who is one of the longest working Honda motorcycle mechanics ,probably in the world. He has made change suggestions to Honda that have been implemented. He knows his stuff. He warned me about not running the K&N filters in my Honda Rancher ATV. Those filters do suck in more dust. The result in off road vehicles is valve problems which result in them not starting and requiring a valve job. I do run a K&N type filter in the Vette, but it gets driven very little and never off the pavement. I would never run one on a daily driver, always on the pavement or not. The gains aren't worth the risk.

 

[Janko]

Driving 2011 Smart Pure in Denver metro area, was getting ~ 39 to 42 MPG on average. Did replace OEM exhaust with Remus center exhaust. It was more compact, less weight, little more sound effects. Did modify OEM intake pipe ass’y that was hard to remove when changing air filter. Simply cut off those three useless chambers & sealed with custom made plastic plugs & screws & epoxy. Each plug made from plastic cutting board/ fitted to opening & sealed with epoxy. Worked great, fix may have improved performance little. Added ScanGauge II to see Coolant temp, RPMs… to make “manual” shifting easier. Air filter was regular paper element in stock filter box.

Using K&N filters should improve any car’s performance, but do not drive in dusty environment!

There are electronic modules that help with engine response and insert at gas pedal harness. Do not remember brand name, but it improved Smart car response somewhat. Do not think this helped gas milage, unlike exhaust & intake mods.