2009 Honda Fit: Wonky MPG Number

Didn't Honda get sued a couple of years ago over inaccurate odometers on it's cars? Does the fuel economy computer use odometer readings in it's calculations? That sounds a bit fishy...

I've never trusted the trip computer of my Mazda3 over my own manual calculations, but I decided to find out how off the trip computer is, so over the past four tanks I've reset the computer after every tank, and I'm surprised by the results:

Manual Calculation / Trip Computer / Difference / Average Speed
26.2 / 25.3 / -0.9 / 25MPH
22.9 / 21.6 / -1.3 / 20MPH
24.0 / 22.8 / -1.2 / 21MPH
25.4 / 24.2 / -1.2 / 25MPH

It's not spot on, but it's close enough, and consistent enough that I can gauge how I'm doing between fill ups somewhat confidently.

Anyway, here's a great website that helps you keep track of your mileage and share it with everyone, it also exports the data to Excel so you can do all sorts of crazy calculations and pretty graphs with it. I've been using it since I bought my car:

http://www.fueleconomy.gov/

Brent's 32.6mpg is the only believable one in that group.

The wildly misleading number from the car computer is something lawsuits are made from. How many people are going to believe the number and make unrealistic claims to the cars mpg? Tons!

smrtypants44, if the odometer were off, that'd screw up your manual calculations too. The only way to know for sure is to count mile markers.

The new estimates are based on closer approximations of real life. However, you should be able to blow them out of the water by several miles a gallon if you follow the slow and steady pace that previous estimates used. The old estimates gave the 1st gen Fit a highway rating of 37-38.

Interesting to see the trip computer so inaccurate. I found that the one in my Lancer read high as well, but no where near this high. A 25% error is ridiculous.

Somthings off here. I doubt honda would allow the trip computer to have a +/- 25% error rate, however, i also doubt that you got over 40 MPG.

this does explain why people who drive Hondas often quote ridiculous mpg averages. I have seen people claim they "easily" get high 30s in the Fit and now I see why. I knew that sounded like BS. The actual reading of 32.6 is extremely good for a vehicle that gets only 33mpg on the highway. How much city driving took place to get that number?

orangutan, I agree with your premise. If he had driven at a constant 60mph, I'd expect a higher number.

He drove 72mph+. He works for Edmunds (lead foot). He passed people. The engine is relatively new (break in period). 32.6mpg makes sense. The other numbers are excessive. 41.5mpg is absurd, especially since his manual calcs said otherwise.

I'm guessing that your methodology for calculating fuel economy is to divide the miles on the trip meter (or the difference between two subsequent odometer readings, same thing) by the number of gallons on the pump? Well, sometimes gas pumps shut off early and you don't get a complete fill up, making the fuel economy abnormally high. When you're working with averages it doesn't matter because they'll usually be followed by a tank of "low fuel economy" (since you didn't get as many miles from the next tank since it wasn't full) but it would create outliers.

I've noticed this happen to me a few times, since I've been keeping fuel economy records of my car since August 2005.

MPG is a pretty fluid concept I'm finding.

I recently took a trip in the 04 Mazda 6i m/t I just got.

I got 537.5 miles out of one tank of gas (w/ 2 gallons left when I filled up), and achieved 33.5 mpg (based on a 16 gal fill up).

The car was originally rated at 34 highway and under the new system (on edmunds) is rated at 29 highway. My driving was a mix of maybe 90/10 city/highway and I probably averaged ~70 mph on the highway. Used the a/c when I had to, but didn't really try any hypermiling stuff except for using cruise to give my leg a break.

If I tried (read: kept it around 65 w cruise on the whole way) I could probably stomp that 34 highway they used under the old system, and if I went 80 the whole way I'd probably be closer to the new number (tach is right around 3k at 75-80). Just goes to show that you can't judge MPG based just on the car. There's probably going to be a 5 mpg swing depending on the driver. And thats if you use the same stretch of road and the same conditions. Some people use cruise and some don't. Some need to go 80 and pass everyone else, and some people set it to 68 and cruise along.

1487,

I don't know about other honda's but my old 07 Fit didn't have a mpg gauge, so people quoting numbers from those cars wouldn't be off.

I also know that if I just drove like normal I got about 35 average. I live in semi-rural area so my driving is a mix of low speed highway jaunts (50-60mph) and block by block stop signs. Most of my driving was in short trips of 4-10 miles. I rarely drove in traffic, though I did make a bunch of 50-100 mile 70+ freeway jaunts and it always seemed to average out to about 35 mpg.

Based on that I would think people, depending where they live, could easily average 37-38 in a last gen fit just like they are saying. I don't know about the new one though.

Now if I didn't drive like "normal" and actually tried for fuel economy I got an average in the low 40s, with a high tank of 53 mpg. My trying for fuel economy meant the following:

Keeping to the speed limit exactly instead of driving 3-4 over.

Shifting at 1500-2000 rpm instead of 2500-3500.

Turning off the car at long stoplights.

Coasting down grades whenever possible, including engine off coasting on some tanks.

Tall boxy cars like the Fit really suffer at higher speeds (mileage-wise). The same when you run the A/C.

Cruising at 60 mph with the A/C off would likely get you near 40 mpg.

I agree with bennetpullen.

I had an 07 Fit Sport A/T (Bought it in November of '06) up until two weeks ago, and it didn't have a MPG computer. My best ever fuel economy was with a tail wind and no AC, and I got 41.6

I could easily get 34-35 in mixed driving if I didn't drive silly. But if I decided to use the gas pedal more, then I'd get 31-ish.

The Odometer stuff with the Fit actually only applied to 07 fits sold before December of 06 and they were only overestimating mileage by about 3 to 4 percent.

The previous generation Fits, for the most part, really did get the mileage that their owners claimed. Regardless of how big a grinding job 1487 is doing on his ax.

Edmunds/IL's normal fill-up procedure is to fill until the pump shuts off, then slow fill until a second shut-off, thereby minimizing the chance of a short fill. -- Brent

I don't go by trip computer mileage and never have - though independent calculations show the 'puter in my Altima to be pretty much dead on. On the one mostly highway trip I took in my wife's Fit where I was able to calculate the fuel economy myself, I got 35 mpg. Speeds were between 115 / 120 kph (71-75 mph). Whether 1487 tinks that is BS or not, I won't pretend to care.

The short gearing of the Fit means that increased speed will quickly diminish average fuel economy. This is where a 6th gear would help. Of course, with any car, moderating speed will pay off big time at the pumps.

"Now if I didn't drive like "normal" and actually tried for fuel economy I got an average in the low 40s, with a high tank of 53 mpg."

I don't mean to play devil's advocate, but 53 mpg seems really really really high.....even if the run happened to be all downhill with a tailwind!

^if it was all downhill w/ a tailwind he would've kept the engine off half the time... there's your 53 mpg!

If the latest refueling put in more gas before cutting off as opposed to the other fill-ups, that would explain the drop in calculated mpg and the discrepancy with the trip computer's estimate.

Doh - clarkma5 beat me to it, and Brent already replied. Nothing to see here, please move along...

Based on my experiences, the new EPA figures for highway mileage are spot on. My Mazda3 is rated at (a pathetic) 29 mpg on the highway under the new standards and was 32 under than old. In realistic highway driving, I get 29mpg. If I drive at an unrealistic 60mph (ie the speed limit) I can get 34 mpg but you are risking your life if you drive that slow on the open road. However, I don't know what critera the EPA uses to calculate city driving because I have never averaged more than 18mpg when 90% of a particular tank is used in city driving. My car is rated for 22mpg in the city and have never been within 4 mpg of the figured and have had many tanks in the 16-17 range.

I don't get the logic of people who think driving the speed limit is "unrealistic." Driving faster is against the law (as well as a waste of money and fuel). Yeah, lots of other people are breaking the law--if you see a bank robbery in progress, do you join it? Just because there's a low probability of being caught and penalized doesn't mean it's OK--the same is true of a lot of crimes.

bc1960

I agree. I see something very wrong about the government setting the standard for mileage based on people who ignore the law and speed.

EPA numbers should be based on driving the speed limit. Those who wish to go faster can figure out their own mileage.

I've heard from just about everyone with an '09 Fit that the MPG calculator in the trip computer overstates things by about 4-5 MPG pretty consistently. There are tons of discussions about why and what to do about this on various Fit message boards.

"I don't mean to play devil's advocate, but 53 mpg seems really really really high.....even if the run happened to be all downhill with a tailwind!"

I was surprised by that one as well. I just pulled my top tank from my old gassavers.org stats for the number. After reading the comments I left it looks like that tank followed an extra low tank so it was probably just equalizing out an overfill.

Another thing though was my single highest trip was 62.4 mpg. That was a 15 minute drive from my girlfriends house home. That trip is in the trees so no tailwinds and with no overall elevation change. I guess that shows if I had just driven that one route for a whole tank some crazy MPGs would be possible.

Anyway I guess the MPGs from Edmunds are useful to see how those cars compare with each other but I wouldn't use them to compare to your own or any other source of MPG numbers.

The new EPA numbers match Edmunds' reported mileage pretty well. If you try a little bit, you should have no problem regularly exceeding the highway estimate. My best 3-tank average for both of my cars beats the EPA highway number by 17%. I'm sure you guys could get this Fit into the upper 30s with more country roads and a lighter foot.

As an owner of an 09 Sport, I think if there is anything off it's the reviewer's FE numbers. They're too low. Doing 72 on a level hwy and only getting 32? Did he/she simply just forget to tell us that there was a massive air brake on the roof?

I commute in L.A. and consistently achieve 34-36 mpg manually calculated. I've done one long hwy trip to Vegas, doing 70 mph with strong head winds and also including some long steep grades and I still achieved 43 mpg.

I'm not the only one obliterating the EPA numbers of 27/33. On fitfreak.net a plethora of owners contributed their mileage on the boards and my numbers are pretty much on target with the others. There are even some that report in the mid-to-high 40s and even breaking into the 50s.

Yes the computer is about 4 mpg optimistic. This is the consensus of all the folks contributing on the website:

http://www.fitfreak.net/forums/2nd-generation-ge-08-present/30682-any-mpg-reports-yet.html

Ok, I can't help myself...

1487 said, "this does explain why people who drive Hondas often quote ridiculous mpg averages. I have seen people claim they "easily" get high 30s in the Fit and now I see why. I knew that sounded like BS. The actual reading of 32.6 is extremely good for a vehicle that gets only 33mpg on the highway. How much city driving took place to get that number?"

I think the resulting replies from actual owners seem to have provided the necessary smackdown to your intellectual prejudice against the Fit's MPG :)

hehe, sorry, it was an easy shot to take :)

Regardless, I'm not impressed with any other Hondas than the fit and civic...but these two really impress me with MPG for their overall engine responsiveness.

I've owned a 2006 Civic SI for over 3 years now and put 61k miles on it. I am blown away by the MPG I get given my driving habits. I just zipped up over the weekend to Rye, NY and back, with a nice stopover in Manhattan involving about 30 minutes of stoplight driving. I cruised at 80 mph (Jersey Turnpike speed of traffic). 30mpg was easily achieved....and that's with 30k miles on my current air filter and 10k miles on my oil without being changed.

The EPA rating for this car, IIRC, is 22 city 29 highway. Yet I get 28-29 in my daily commute which involves very aggressive acceleration, numerous trips to redline, 10 miles of stoplights, and high speed cruising.

I definitely like the new EPA averages alot more (my wife's Legacy GT is spot on with them)....but, for some reason, some cars seem to be able to easily exceed the EPA highway rating.

Joe

"On the one mostly highway trip I took in my wife's Fit where I was able to calculate the fuel economy myself, I got 35 mpg. Speeds were between 115 / 120 kph (71-75 mph). Whether 1487 tinks that is BS or not, I won't pretend to care."

Why would I doubt a 35mpg HWY figure that is very close to the Fit's rating? That makes no sense. My issue is when people (and they tend to be Honda owners or hybrid owners) offer up mileage that is 10% better than EPA highway numbers and then claim they got it in mixed driving. I can believe a Fit averages low thirties, not high thirties in true mixed driving. If you live in rural Iowa and your city driving consists of two lane road with little traffic you arent really doing much "mixed" driving.

"I think the resulting replies from actual owners seem to have provided the necessary smackdown to your intellectual prejudice against the Fit's MPG :):"

I cant resist: How many people said they easily get 38+mpg in the Fit in mixed driving? Not many according to what I read above. If you notice, it always seems like people who happen to own fuel efficient cars are the ones who have a problem with the EPA ratings system. When it comes to larger cars most people have found the system to be relatively accurate. As soon as we start talking about a Fit or Prius you get fanatical owners calling the EPA's system a joke and claiming they are getting 45mpg in the city. Why would the EPA's system be accurate for most cars but not for the Fit?

bc1960:

First of all the speed limit isnt 60 on most interstates. Secondly, that is not a realistic crusing speed on today's highways. There is not a huge difference in efficiency between 60mph and 70mph so I dont think we need to stick to artificially low speed limits to save fuel. My car is capable of 28mpg at 70mph and its rated at 26mph highway. Driving 60mph on a wide open highway is borderline dangerous and its definitely annoying to other drivers trying to move with the flow of traffic.

"I definitely like the new EPA averages alot more (my wife's Legacy GT is spot on with them)....but, for some reason, some cars seem to be able to easily exceed the EPA highway rating."

If you drive slow and leave the AC off you can exceed the EPA highway number for ANY car. Cruise at 55 and you will certainly exceed the EPA number.

I dont think IL would be doing us any favors by driving differently in the Fit just because its a small car. They should drive the same way in all their vehicles and report the numbers. People are mad because they are exceeding 50mph on the highway and not reporting 40mpg on road trips. If Fit owners chose to drive in a super conservative manner so they can talk about averaging 38mpg or so on the highway that is their choice but dont expect IL to do the same.

"Anyway I guess the MPGs from Edmunds are useful to see how those cars compare with each other but I wouldn't use them to compare to your own or any other source of MPG numbers."

Most magazines that test cars for a year get results that are consistent with IL's. It seems like the primary issue here is that people who are huge fans of their cars seem to cry foul when IL reports anything close to EPA mileage for that particular vehicle. BAsed on my experience with my current car and others, their numbers seem realistic. I just drove 300-350 miles over the weekend and averaged 25.4mpg in 90% highway driving vs an EPA rating of 26mpg. I dont see how so many people are beating EPA numbers by 15% while driving 75mph. It makes no sense.

"People are mad because they are exceeding 50mph on the highway"

Who said 50 mph?

"I've owned a 2006 Civic SI for over 3 years now and put 61k miles on it. I am blown away by the MPG I get given my driving habits. I just zipped up over the weekend to Rye, NY and back, with a nice stopover in Manhattan involving about 30 minutes of stoplight driving. I cruised at 80 mph (Jersey Turnpike speed of traffic). 30mpg was easily achieved....and that's with 30k miles on my current air filter and 10k miles on my oil without being changed."

Joe, our secretary has an 06 Civic LX Coupe 5AT and she recently took a trip to Florida from Ky. She stated she kept her speed between 70-75, no A/C and consistently got 40-42 mpg highway. Keep in mind shes a very conservative driver, her Civic has around 27,000 miles and her maintenence records are all RELIGIOUSLY up to date.

"this does explain why people who drive Hondas often quote ridiculous mpg averages."

1487, PUHLEEZ! Ive heard from people who drive various brands of cars report rediculously high or low MPG figures, its not just Honda owners who report unbelievably high fuel milage. Even you CONSISTENTLY brag or bring up the Chevy Cobalt FXEs (or whatever its called) fuel milage and to my knowledge, dont even own one. People should consider that "paper performance" doesnt always equate to REAL WORLD performance regardless of brand.

People also need to realize the EPA numbers reflect the EPAs own driving techniques, which are more than likely going to differ from the owners own style. Sure, the EPA has seriously upgraded their testing procedures to better represent current average driving styles but no one can match the EPAs procedures 100% of the time.

Fuel efficiency is one area of performance that can be easily changed by 1 element or a number of elements. Weather, wind, vehicle aerodynamics, temeperature, elevation, maintenence, tire pressure, road conditions, vehicle milage and most importantly road conditions and driving styles all play a serious role in gas milage. With so many factors involved why do so many drivers complain when their own fuel milage doesnt match the EPA estimates?

Look around this site. I recently took at look at some consumer reviews on full/midsize V8/large V6 trucks from GM, Toyota and Nissan. Almost all of them (mostly Nissan truck owners who complained) complained about gas milage even though some matched or exceeded the EPA estimates. What were they expecting from a truck, 35MPG? People have to realize that there is a lot of gray area when it comes to fuel milage.

"1487, PUHLEEZ! Ive heard from people who drive various brands of cars report rediculously high or low MPG figures, its not just Honda owners who report unbelievably high fuel milage. Even you CONSISTENTLY brag or bring up the Chevy Cobalt FXEs (or whatever its called) fuel milage and to my knowledge, dont even own one. People should consider that "paper performance" doesnt always equate to REAL WORLD performance regardless of brand."

I rarely talk abou the XFE. The XFE's mileage ratings come by following EPA test procedures. It is perfectly logical to compare EPA mileage ratings. Its not logical to compare anecdotal mileage amongst various people when you dont know how people arrive at those numbers. I did not say its ONLY Honda owners that do this, but since Honda has a reputation for fuel efficiency you seem to find Honda owners being more fervent in their defense of sky high mileage figures. This is also the case with hybrid vehicles. Even though the press has routinely gotten mid to upper 40s for the Prius those who drive the Prius swear that with no effort you can average well over 50mpg.

The 2009 did have a bug in the mpg calculator and came out with a patch for it. I have a 2010 Fit Sport and am finding the mpg meter to be very close to my manual calculations. On one of my first tanks of mixed driving I calculated 31.9 and the mpg calculator said 31.7. On my current tank the calculator is at 36.2 after a nice drive down to Monterey Bay and back from the SF Bay area in light traffic moving between the speed limit and 10 over. I am very very impressed on the economy of this car!

From other Honda Fit forums it seems mine is typical.. higher actual mileage than EPA estimates are easy to achieve if you don't floor it a lot or sit in traffic constantly.

These are real figures based on actual fuel used and odometer readings of a stock, 2008 Honda Fit, with manual transmission, 15,000 miles on it, and the A/C always off:
My daily 6.5 mile suburban commute, stop-and-go, max speeds 45 mph: 37.8+/- mpg.
Traveling on the highway at 70 mph, including several miles of stop-and-go before and after the highway: 36 mpg.
Traveling on the highway at 55 mph, including several miles of stop-and-go before and after the highway: 49 mpg.
To quote John Wayne; “Life’s tough . . . it’s even tougher if you’re stupid” (especially with gas at more than $4 per gallon).