Okay, my estimates say I'm doing about 30mpg when converted to US and 36mpg when I convert to UK. Think I'll stick to the UK conversion and feel happy about it...placebo effect, haha.

 

I'm wondering what you all are experiencing with regards to the gas mileage that's being calculated and displayed on the touchscreen console. Are you finding it close or far off from what you would otherwise calculate manually? I notice that it always reports better than the actual calculated. By 2 gallons or so.

I wonder what algorithm is used to calculate the value because if done manually its: Amt filled/trip distance.

 

The best I can really average in the city here is about 35mpg, and that's if it's not a particularly high-traffic time of day. Highway rides can easily manage over 40mpg, sometimes closer to 50mpg if the conditions are right. It's capable of pretty great fuel efficiency, even driven by someone who lacks patience (me) and even in an area with a lot of stop-and-go traffic.

 

Seems I would too. I reset the trip meter this weekend and found that over the course of three trips - about two hours total drive time - I clocked 8.8L/100km. On those trips there were two ten minute periods of idling with the A/C on (waiting for people - too muggy and hot in the car for my wife to forego the A/C, though I might try rolling all the windows down next time instead), along with about 40 minutes of near-gridlock, where I had to keep the engine running because we were moving every thirty seconds and failure to move when a car length opens up in front of you means getting cut off by some idiot who thinks he can move faster in your lane. Driving to and from work can be bad, but on my commute this morning, representing about 10% of the total distance since I reset the trip meter, I dropped the average from 9.1 L/100 to 8.8 L/100, so given the right situations, I can do better.


Time for more experimentation!

 

I would be so frustrated if I had to drive in those conditions. It sounds like you must have a lot of patience, well, hopefully you do because you need it. You're no doubt doing about as good as you can.

 

My dash gauge is basically 3%-5% higher than my actual calculation. Keep in mind though that you can't really expect to fill your tank exactly the same each time, and even a tenth of a gallon difference in filling changes your mpg calculation.

For example:
Lets say you drive 400 miles and fill 10 gallons, your mpg = 40.0
Now, say you added 10.1 gal instead of 10.2, mpg = 39.6 (1% less than 40)
Now, lets say you squeezed in 10.2 gal, mpg = 39.2 (2% less)

There are just so many variables in tank to tank fill calculations that comparisons aren't always going to be apples to apples. That's why I have the 3-5% range mentioned above as opposed to a finite number.

 

I'm old enough to remember when they set the speed limit to 55mph to save fuel across the country. There was an engineer who came on some TV station at the time and said that the optimum fuel efficiency is actually at 53mph and the government rounded that figure up to 55mph for signage etc.

I wonder if 53mph still holds true today as the optimum speed for saving gas?

 

The optimum speed is different for every different combination of engine, gearing, tires, weight and aero.

With higher speed limits and more awareness of mpg, many models probably do better at higher speeds now.

But it's ~45 for a lightly loaded GE with a manual.

 

There's more to life than another 1 MPG. Sitting in a car with music and A/C is better than opening the windows and suffering. If conditions are right, I'll shut off the car at lights I know stay red for close to two minutes. I know when they're about to turn green, so I'm not holding up the cars behind me. I don't want the car behind me to start through the intersection before I do.

 

Computer in car seams optimistic from Fuelly... I'm only 1700 miles in.. so not ready to post up claims yet..

 

For sure - the only adjustments I'm making to get better mileage are those that make sense for comfort and transportation purposes. Sometimes having the windows open is enough to make up for not running the A/C. Sometimes shutting off the engine at long lights is worth it (most lights here have a timer displayed that gives you a nine-second heads-up when the light's about to turn, which helps). I won't do the latter when my wife's in the car because it would drive her crazy, but when I'm solo, it's worth it.


Being new to owning a Fit (and let's be honest, I haven't owned a car or driven regularly in eight and a half years), it's good to get tips and advice to help improve mileage, and I'll be experimenting to see what works for me and what I'm not willing to do or give up for a few extra MPG. I'll probably eventually settle on a combination of behaviors that gives me a couple MPG more than I would get driving any old way, and that might not really be a big deal financially, but I like to be deliberate and well-informed about the way I do things, so this process helps me even if the end result probably won't make much of a difference.


Funny fuel-saving story: we were in a crappy 12 passenger, 1.4 liter van with some friends a few months ago, rolling down a fairly crowded expressway, and the driver was driving me up a wall. She would slowly accelerate to the max speed limit, then pop the van into neutral and roll for twenty or thirty seconds until she was well below the minimum limit, then do it again. She did this the whole trip, inconveniencing tons of drivers who had to keep slowing down and speeding up behind her while she did this, and indirectly causing a lot of dangerous driving as people would go to the shoulder to pass her. Considering that she kept accelerating to the speed limit before going into neutral, do you think she was even saving any fuel driving like this? Either way, I wanted to strangle her.

 

I wish we had timers on lights here. That would be great. Be aware that after shifting the car into D, it take a moment before it's ready to go, so you have to wait, rather than just hitting the gas.

Since someone here recently mentioned coasting in neutral, I've been doing it on long down-hills if there's no traffic behind me. It makes a big difference, but you need a long enough stretch to make it worthwhile.

Studies have shown that having the A/C on gives better mileage than having the windows open - at least at highway speeds. I've never been able to measure a mileage difference between A/C and non-A/C. Leaving the A/C off and sweating on a hot day is ridiculous. You have to decide what's important - bragging about a high MPG figure or saving money. Making one less trip into town will save you more money than all the mileage tricks combined.

Warm weather and a warm engine are a huge help in getting high MPG. As for that woman shifting into neutral, she's an idiot.

 

You ever hear that a little knowledge can be a dangerous thing? She'd heard of a technique called pulse and glide. It works, but not in every situation, and that was one of the times it doesn't work. In fact, she was probably getting worse mileage than steady driving would have gotten her. On unaerodynamic vehicles it's a bad idea. The engine has to work too hard getting up to speed and then the van decelerates too quickly to see any benefit in the glide. On underpowered vehicles the penalty is even worse. And that's not even getting into the mess she was making of the road- causing congestion and trying to force accidents is always a bad idea.

 

Hard to argue with that.

 

yeah P&G is hard enough to do on NJ Highways without being a complete douche and holding up traffic.

 

P&G works its best in a hybrid, when the glide portion is done entirely without the engine running. It can also be very effective with a MT if you can safely cut the engine during the glide. But yeah, doing it in heavy traffic is ridiculous and only gives hypermiling a bad name.

Re the stop lights with timers, I agree, I would love for all lights to have those. At this point we only have a few, but they really help with "light timing."

There's been so many studies, opinions and reports as to which is better at highway speeds, windows down or a/c on, that it will just set your head spinning. Because the Fit has such a small engine, I try to keep the a/c off as much as possible since it will have more of a negative impact then say a V6 or V8. At highway speeds, I'll open the windows up 1/4 of the way.

 

In heavy, erratic traffic it's not hypermiling so much as warming up for a demolition derby.

 

My wife noticed this LX mileage thing when she first looked at the 2015 Fit. She went with the EX-L anyway and here is what we now know after about 1K miles:

Around town: 33-36 MPG
Highway: 42-45 MPG

Of course you can lead foot it and drop that, but those numbers are pretty easy to obtain. I don't spend much time wondering why the test results come out the way they did. Our experience would indicate that the question should be why is the rating low on the EX, not why its high on the LX.

 

Our experience is that it reads around 2 mpg higher than actual, so close to the 5% that GoBucky reports.

 

On regular gas, mine is 2 to 3 mpg optimistic. On premium, it is only about 1/2 mpg optimistic. I have used the Car Logbook app since new, a little over 5,000 miles.