I'm still fiddling with mine. Can NOT find a correction factor that provides accurate results. I'm at 0.55 right now, which puts it close . . . sometimes.

The instantaneous number is handy for determining habits to improve fuel economy - but don't get one to track mpg.

 

Do you have an AT or MT? GD or GE?

In my case (a MT GD), a "sweet spot" is more like 3500 rpms. At anything under 3k rpms I almost always get better mpg using the next gear down. For example - at 45mph, 3rd gear is much more efficient than 4th. And if I recall correctly, 3rd gear @ 45 is more than 3500 rpms . . .

 

This is on a 2007 Fit 5 speed. I have not made an effort to observe runs higher than about 3000 rpms and see what the kiwi reports as I have had a sense that for me higher than about 3000 or 3200 rpms is dipping lower in mpg - but I have not looked to hard at those higher rpms. I may be wrong about >3000k being even better.

I will try to take better care to compare. Unfortunately the kiwi does not log, so one has to watch constantly.

If I have a chance when the weather stabilizes (windy and rainy now), I may be able to try some cruise control drives at various speeds and gears on a mostly flat road section which would give a better result (about 5 miles of road is usually vacant for such in the PM nearby). I can reset the 'avg' mpg for each 5 mile run which will smooth things out. If no one is there, I should at least be able to do a 35 mph to 55 mph series in various combinations.

Even if the kiwi calibration is still not perfect, it will give relative results just fine.

Assuming the kiwi is right, it sure makes a huge difference and even though engine breaking is more for the lower gears when you take your foot off, it seems that the lower the gear the better for mpg on the whole (unless a serious downhill coast is in progress).

 

First:

I had the Kiwi mpg left in standby mode. The fit sat for a few days like that. Then today, fit would not start and the Kiwi said 'conn err' or something like that. I took the Kiwi out and jumped it successfully, but it was unclear if the battery really was low or not. No error codes. When fit did not start no lights (like the ODO display came on with the key on).

Second:

With regards to the best rpm for mileage, I drove a bit on some flat stretches in 2nd and for my 07 manual the kiwi claimed that my mpg was better at about 3000 to 3200 than at 2500 to 2800 rpm.

I have not tried other gears.

The little engine makes some noise cruising around like that, but if the kiwi is right it makes a big mpg difference!

 

Yeah, I've just about given up on finding an accurate setting for this thing. With my correction factor set at 0.54, it was about 4 mpg optimistic on a highway trip, and 1.4 mpg pessimistic on my latest tank of city driving.

With the trip mpg so unreliable, I'm having a hard time trusting the instantaneous reading.

 

Eh, you have to guess/calibrate this thing first? I was looking at it but knowing that the numbers won't be 100% accurate kind of nullifys the point of getting one.

 

I don't know about other applications . . . but yeah. Out of the box, it's not even close to accurate. And after months and months of trying to get it calibrated, it's still not right.

I just finished another tank a few days ago - Kiwi said I'd got 21.8 mpg, when I actually got 24.9. This is on the same setting that was so wrong in the other direction on my last highway trip.

 

That really blows. My wife has an iPhone, so I was looking at the iPhone variation so she could keep an eye on her MPG. I guess I could just fiddle with it like these guys have as I know it gets around 35-36 on the freeway....still sucks though.

 

I know I'm zombie threading this, but does anyone have one of the bluetooth dongle's and android apps?

 

Yes I run the "Torque" app on my android phone along with an ebay bluetooth adapter. That setup can do everything you could ever hope for and more! Datalog, fuel, fuel trims, mock digital gauges for anything from IAT's to coolant temps to gps speeds to long term and short term fuel trims etc... you get the idea it will even read boost off of manifold pressure! It's pretty much the best thing about having a smartphone. You can even datalog google map a "track" and save it! 0 to 60, 1/8th, 1/4 mile, HP, TQ does everything.

Torque — OBD2 Performance and Diagnostics for your Vehicle