I bought my Fit new last June. Driving a mixture of city and highway, I got 39-40 mpg for the summer months, exactly what Consumer Reports results were, and the reason I bought the car. However, in October, mileage started dropping, getting to its lowest point in January-February - about 27-28 mpg. It lost 25% of its mpg. I traded in a 2001 Civic with 200,000 miles which got better mileage than this new Fit in winter, driving the same exact route, day in and day out. The Fit’s tire pressure has been checked and rechecked, brakes checked for any area of drag, air filter changed (twice), and the thermostadt was tested. A dealership “checked the codes in the system” and said there’s nothing wrong with the car. They told me city driving is taking down the mpg, which makes no sense since I’m comparing it to the same daily route I’ve had for 6 years, and the Fit got 40 mpg on that SAME route in the summer. So, is there anything that can be adjusted or looked at that could recover some of the 25% mileage drop in cold months? I also changed to mid-level gasoline. No effect. My Civic lost 3-5 mpg when it was really cold, but this car drops 5 mpg when it’s BELOW 70 degrees!! Yes, I’m maintaining a log, and not just relying on the car’s odometer calculation. I wish I’d never bought it at this point, and I feel cheated that the mileage statistics are is only valid if the weather is over 70 degrees, which is crazy. Anyone have any suggestions? Sell it in Florida?
How are you measuring the gas mileage? The only good way to measure mileage is to divide the number of miles you’ve driven since the last fillup by the number of gallons you put in. If that’s not how you are doing it I recommend starting a new log using that method.
Gas companies change the formula of their gas between summer and winter, which can effect mileage, especially if you’re burdened with ethanol-contaminated gas like a lot of us are. That garbage has much less energy than normal gas, and therefore you have to burn more of it to get the same result.
The colder air also effects mileage, as it is more dense, and the car’s computer picks up on that and squirts more fuel in to maintain the proper ratio.
You didn’t mention how far you are driving on a routine basis, but if you take a lot of short trips, a mileage drop in the 20% and sometimes more range when winter strikes is not unheard of.
Also, are you filling up at the same station? Are you running the car more when it’s stopped (starting it 10 minutes early so it’s warm by the time you get in/leaving it running when waiting somewhere so you don’t get cold, etc)? Driving differently in any way at all (spinning tires on ice, driving at different speeds due to road conditions, getting stuck in more traffic because other people can’t drive in the snow, etc)?
If you go through all these questions and still haven’t found a viable culprit, then you should jack the car up so that all 4 wheels are in the air, put the transmission in neutral, and spin the wheels by hand yourself. See if any of them are dragging.
All that said, I don’t know which engine/transmission combo you have, but one version of the Fit is EPA rated at 32mpg city, which means 26mpg city in the winter is entirely reasonable and you are getting bonus mileage in the summer. The best-rated Fit gets 36mpg according to the EPA, so you are still getting better mileage than you should be in the summer. Hopefully that helps reduce a little of your annoyance at the situation.
Also, transmissions and differentials have oil that has higher viscosity in the cold months, which causes more drag and lower MPG.
My Subaru Forester (which is all-wheel drive, and thus more differentials) has the mileage drop from 34 to 28 in cold months. This is over a fixed drive I make frequently at a fixed speed. That is 18%.
If the mileage goes back to what it was last summer by June, there is probably nothing to do but enjoy this great little car. Do the math; a difference between 30 and 35 mpg over the Winter months is peanuts.
“They told me city driving is taking down the mpg, which makes no sense since I’m comparing it to the same daily route I’ve had for 6 years”.
Actually, it may very well make a difference. It’s possible that the Fit engine lacks the power to overcome the added resistance in the cold powertrain fluids in the winter. Perhaps also the powertrain fluids are taking longer to warm up than your Civic did.
It’s also possible… and this is very likely… that the fit’s smaller engine takes longer to warm up and it runs richer longer, killing gas mileage.
I hate to say it, but you’ve done everything you can to be sure there’s no problem with the car, and I’m afraid you’re stuck with this performance. Perhaps it’s time for manufacturers to begin posting “cold weather mileage” both city and highway.
Not a fit but I have a trusted guy, gas mileage down, waiting to see the result as I am on first tank, but the fuel pressure regulator was spewing gas into the intake manifold, bad diaphram, just to say a proper diagnosis for a proper repair. no cel or other symtoms in my case
Good idea above , see if the problem resolves itself with warmer weather. If so, that’s probably just the way newer Fits work.
If it doesn’t improve to the prior mpg as the weather turns warmer, mpg is most sensitive to the coolant temperature, so here’s where I’d start
-
Replace the thermostat. They can seem to be working, the dash temp gauge can look normal, but in actuality they are leaking a little or opening at a slightly lower temperature than they should. That will cause the fuel injectors to put out more gas than is needed. Thermostats are cheap and usually easy to replace. I had a thermostat with a similar problem on my Corolla, very difficult to tell it was actually not sealing properly and a little, causing the engine operating temperature to be lower than it should. Sort of hard to believe this would happen in a 2015, but it’s an easy enough experiment to do. Good idea to check both thermostats – new and old – in a pot of hot water on the stove too to visually verify what temperature they open.
-
Check the engine coolant temp sensor used by the computer to adjust the fuel/air ratio vs temperature. Those are usually just thermistors which are pretty robust, but I suppose one could fail and register an incorrect coolant temperature. Should be easy enough to check, just remove it and measure the resistance vs temperature and compare to the specs.
-
Next up, either take it in for a proper diagnosis, including fuel pressure, or if you feel lucky, replace & gap the spark plugs and plug wires.
@Barkydog You have a trusted guy that bought a new car with a fuel leak? If the OP has a fuel leak they would likely know about it.
The March 2015 issue of Consumer Reports rated the Honda Fit at 33 MPG, lower fuel economy is normal and expected during cold weather.
Manufactures are required to equip cars with self diagnostics that identify a failure that can cause the vehicle to produce emissions 150% of federal standards. If your vehicle has a failing thermostat of coolant temperature sensor your check engine light should be on.
“However, in October, mileage started dropping, getting to its lowest point in January-February - about 27-28 mpg.”
“I wish I’d never bought it at this point, and I feel cheated that the mileage statistics are is only valid if the weather is over 70 degrees, which is crazy.”
Yikes! I don’t blame an owner for being extremely disappointed by this performance! I have a Bonneville, Grand Prix, and an Impala that can meet or beat those MPG figures and I get to ride in a quiet, comfortable vehicle with lots of room. My mileage doesn’t vary that much by season.
That’s one reason I won’t buy one of those little economy cars. To me the MPG or expected MPG stuff just isn’t worth it (and I’m very thrifty cheap).
Also, I am not a disappointed owner. I know what to expect. I am very "gruntled."
CSA
I suspect CAFE standards are all run at room temperature…
That is unfortunate, and should be changed. But the odds of that are low…
@csa My Corolla uses nearly twice as much gas in winter stop & go driving that in summer highway cruising.
If you want to increase your Fit’s gas economy, install an engine block heater with a timer to come on 1.5 hours before you start the car. Also, parking in an insulated garage helps a lot.
I have seldom met a car owned who really loved his car because of its gas mileage alone. A friend, a veteran who drinks 20 year old Scotch, bought his wife a Fit, which she really likes for shopping and city driving. That’s what this car was designed for. Their main car is an SUV.
The Fit is a poor highway car, which Consumer Reports has pointed out. It still has a very high rating for reliability and versatility. Kids can carry surf boards in them with the passenger seat down.
@Docnick
"Kids can carry surf boards in them with the passenger seat down."
You made me laugh… I recently read that my little Grand Prix (photo at left) can carry a kayak when the rear seat and front passenger seat are folded. Picture it. 
Back when Earth began cooling, I had a VW bug and I’d remove the passenger front seat (took like 2 seconds… unhook a spring and slide it out) and I would easily carry a Honda Trail 50 motor bike in there! :neutral:
CSA
One of the most fun things about small cars that are hatchbacks is how deceptively huge their cargo capacity is. I once won a bet with a lumberyard loader at a hardware store who said I’d never get that 36" rolling toolbox in my little CRX. I did, and the hatch even closed.
We’ve got a Veloster now and before we got our little pickup truck, it was the pickup. We’ve gotten entire yard projects in it in one load before. People sometimes would stare at how much we’d stuff in there and still have room for a little more.
It is,normal for gasoline mileage to drop in the folder months. I don’t think a 25% drop is abnormal. Did both your Fit and Civic have automatic transmissions or was one a manual and one an automatic? Is ir possible that the compressor for the air conditioning didn’t come on in the Civic in the defrost mode while it does in your Fit(as it should)? Was the winter in your area more severe actions than previous wiinters? Perhaps the gear ratio for around town driving is lower on the Fit than it was on your Civic.
My guess is that your mileage will go back up in the warmer months and you have nothing to worry about. One other thought: have your driving habits changed from the way you drove the Civic to the way you now drive the Fit? Who else drives the car besides you? I say this because I had a Ford Aerostar when our son was a teenage driver. When he drove the Aerostar, the gas mileage was always better. He has a very calm personality and it was,and still is, reflected in his driving.
@csa Yes, hatchbacks are very popular in Europe and elsewhere as family cars and haulers. My son’s wife has a Toyota Yaris hatchback. She bought a freezer at Costco and actually brought it home in the Yaris with the rear hatch closed.
My wife’s Mazda Sport holds 2 bikes with the rear seat down.
I own a Mazda6 that can get up to 40 mpg on the highway. A heavy foot induces much lower numbers. I also know that small cars with smaller engines can get even worse mileage with a heavy foot since the small engines work even harder than a larger one to produce acceleration.
@Nevada_545 The trusted guy is my mechanic, the car is my 03 with 177k, a bad diaprham in the pressure regulator was leaking fuel int the intake, no cel, no symptoms,just lookingfor reasons the gas mileage might have been down for the last few years. I thought it was moving off michelins, put meichelins back on but mileage wsa still 2 to 3 gpm less than it used to be.
Leaking out what I assume to be a vacuum hose connection on the top
Differing fuel chemistry aside… I would sniff the tailpipe after the vehicle is HOT…If it smells like raw or unburned fuel… Its time for new O2 sensors…they play a major role here…
If the correct O2 sensor goes out to lunch the fuel injection will default to full rich…and bye bye mileage numbers…
Id replace the O2 sensors, post haste…but thats me…
Blackbird
@Docnick
"My wife’s Mazda Sport holds 2 bikes with the rear seat down."
Wow! Not bad! I’m impressed.
I haul bikes all the time, either as you describe or in my Caravan.
Almost all the time I carry two Dahon (named for David Hon) 8-speed aluminum folding bikes in the trunk of my Bonneville or Grand Prix , without folding down the back seat, and can shut the trunk.
I take those Dahons because sometimes I see a fun place to ride, need to kill time, or an impromptu ride comes up while visiting my kids and other friends and relatives. I love those bikes. They perform just about as well (speed and efficiency) as my full-size bikes, and are very comfortable.
CSA