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Wow, whats that like 2 tanks of gas? Cant help but think of the saying your insight was getting more *** time than a rental car. :evil:
 

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I drove over 1000 miles over four days, and averaged 51.4mpg.
Congrats on your high mpg skills. Any tankful at an actual 50 mpg or better (not the dashboard gauge which runs +3 mpg over the actual mpg), is more than just good fortune, there's good high mpg driving skills in the mix as well!
 

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seriously wonder how people can manage to get that much mpg on the Insight...

My 500+ mile round trip from the Bay Area to SoCal resulted in an average of... 35.6 mpg (1st tank - 38.2; 2nd tank - 33)
 

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The bay area must be full of stop lights? I had a week off from work, just driving around the community I live with the AC on I averaged 39 on the mid. Next week I went back to work I was back at 45 on the mid. Of course that means keeping with traffic and driving with the AC on.
 

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The trip I had was mostly freeway with hills, high speed, etc. And some city driving, maybe ~50 miles worth of city. AC was on most if not all the time.
 

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Is there a way to adjust the gauge for accurate mpg? Isn't that false advertising?Is odometer off too?
 

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The odometer / speedometer over-read so I would dispute 'actual'. Therefore the truth lies somewhere higher than what you calculate from fuel receipts vs mileage.
I'm not familiar with the "odometer / speedometer over-read" that you refer to. Am wondering how much that over-read is?

I also note you are in the UK and so two factors come to mind; (1) Here in the states many areas have very strict rules preventing tampering with the odometer of all vehicles. This is because of our history of thievery in the car resale market, and technical tax issues. (2) A gallon of gasoline in UK is a different volume than a US gallon.
Also: (3) Some people put larger circumference wheels or tires on their car, altering the odometer / speedometer accuracy. This would be a special case circumstance in which the "actual" for most, would not apply.

Given all the above, what language would you suggest as an alternative to "actual", ...to identify and lablel the common process of calculating mpg from fuel receipts and odometer based mileage?
 

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Is there a way to adjust the gauge for accurate mpg? Isn't that false advertising?Is odometer off too?
I complained to Honda about this several times. Nothing has been done. I've since learned that it is technically difficult to get it accurate. However my wifes I1's gauge is consistent to within 0.05 mpg with fuel receipts and odometer based mileage figures.

I believe that the odometer and speedometer are sufficiently accurate. I believe the error in the mpg gauge readout has to do with the measurement of fuel flow / fuel used by the engine.

I once compared mpg from the gauge with mpg from fuel receipts and odometer readings. I did this for 5 tankfuls. The gauge averaged 2.93 mpg higher than the hand calculated mpg, per tankful. As a practical matter I assume the gauge mpg is 3 mpg high. I assume the miles to go before you run out of gas screen, is too high and untrustworthy.
 

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My speedo overreads 3-5% . Underreading speedos are illegal over here btw, all have a safety margin on the plus side.
My odo underreads very slightly, I guess it will be spot on as the tires wear.
The FE meter is quite optimystic but as it shows l/100 km with just one digit behind the decimal point it is hard to put an accurate number on it.

You can get a decent FE out of the G2 when you stay in the slow lane like I do.
Had a 3.2 l/100 km average on my commute the other day (by the MID) which tops 70 real mpg (US) even when taking the underreading FE meter into account. I felt it was on the edge of jumping to 3.1...

Here's my fuel log on Ecomodder for who wants details.

 

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My speedo overreads 3-5% . Underreading speedos are illegal over here btw, all have a safety margin on the plus side.
My odo underreads very slightly, I guess it will be spot on as the tires wear.
Congratulations on your 53+ average mpg US, over 23k+ miles. I'm currently at 50.4 mpg US for 60k+ miles. How do you do it? Am always looking for ways to do better. I've found best mpg happens in the 35 -50 mph range on a flat road. Were I able to do that for most of my driving, I may have a chance to catch up to ya. :) FYI see Blue Bird (Honda Insight) | Fuelly

Didn't see any data supporting your speedometer over read or under read of odometer though. Where do those numbers come from?
 

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Honda have previously settled a class action lawsuit for odometers over-reading in 2007. Over-reading meant that they granted warranty extensions amounting to 5% of the recorded mileage for affected users. While they never actually admitted over-reading, perhaps they subsequently over-compensated by a slight under-read? See this link:

http://www.odosettlementinfo.com/Vaughn Final FAQs.pdf

Speedo over-reading is down to compliance with United Nations Economic Comission for Europe (UNECE) regulations. To summarise:

As with the UNECE regulation and the EC Directives, the speedometer must never show an indicated speed less than the actual speed. However it differs slightly from them in specifying that for all actual speeds between 25 mph and 70 mph (or the vehicles' maximum speed if it is lower that this), the indicated speed must not exceed 110% of the actual speed, plus 6.25 mph.
Speedo Accuracy - Fleetco
 

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Congratulations on your 53+ average mpg US, over 23k+ miles. I'm currently at 50.4 mpg US for 60k+ miles. How do you do it? Am always looking for ways to do better. I've found best mpg happens in the 35 -50 mph range on a flat road. Were I able to do that for most of my driving, I may have a chance to catch up to ya. :) FYI see Blue Bird (Honda Insight) | Fuelly

Didn't see any data supporting your speedometer over read or under read of odometer though. Where do those numbers come from?
Thanks :)
I see you do a lot of city driving, that is killing unless you have long stretches of 35(ish) mph in that.

What do I do. I bring the kids to school in the morning (1 km city driving), then 5 km mostly rural and 30 km of highway for the last km of city driving at work.
Back home either the same route the other way or skipping the rural bit for 3 extra km of highway and 2 extra city driving, which is quicker but slightly less fuel efficient.
I generally stay in the right lane and keep behind whatever drives there unless it makes me feel unsafe. Usually I end up behind a semi doing 80-90 km/h (50-55 mph), at a respectable 2-3 second distance.

I run just over 3 bar (44 psi front, 42 back), have a lower grill block and a wing sleeve over the antenna, extra brake pad return springs on the front brakes (now pairs instead of OEM singles).
Oh, and I use solar engine heating; I park facing west so the sun heats the engine bay somewhat (I use window shades to prevent being cooked alive on my way home), that can easily raise the engine temperature for a few extra degrees, allowing autostop even at the first set of lights.

I reset my B counter at every cold start, so I know the length and economy of each trip.
Both my TomTom and Google Maps show the route I drive to be slightly longer than the MID shows, but it deviates less than 1%.
The speedo typically shows about 3 km/h more than the GPS does at 80 km/h (ish) hence the 3-5 % overread on that.
My fuel log is based on odometer reading and actual tanked volume by the pump gauge, except in the case where that was known to be underreading (!)

The odometer deviation is the same for both my 175/65/15 Continental winter tires on steel rims and the 185/55/16 Bridgestone summer tires on the 7 spoke alloys; the latter have a little bit more wear so I suspect they are actually very slightly bigger. I run the same pressure on both, except under icy road conditions (then close to OEM). The higher pressure may also explain the underreading odo meter for 0.1 of a % or so.
 

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Thank you Uriel, for the info.and links!

What do I do. I bring the kids to school in the morning (1 km city driving), then 5 km mostly rural and 30 km of highway for the last km of city driving at work.
Back home either the same route the other way or skipping the rural bit for 3 extra km of highway and 2 extra city driving, which is quicker but slightly less fuel efficient.
I generally stay in the right lane and keep behind whatever drives there unless it makes me feel unsafe. Usually I end up behind a semi doing 80-90 km/h (50-55 mph), at a respectable 2-3 second distance.

I run just over 3 bar (44 psi front, 42 back), have a lower grill block and a wing sleeve over the antenna, extra brake pad return springs on the front brakes (now pairs instead of OEM singles).
Oh, and I use solar engine heating; I park facing west so the sun heats the engine bay somewhat (I use window shades to prevent being cooked alive on my way home), that can easily raise the engine temperature for a few extra degrees, allowing autostop even at the first set of lights.

I reset my B counter at every cold start, so I know the length and economy of each trip.
Both my TomTom and Google Maps show the route I drive to be slightly longer than the MID shows, but it deviates less than 1%.
The speedo typically shows about 3 km/h more than the GPS does at 80 km/h (ish) hence the 3-5 % overread on that.
My fuel log is based on odometer reading and actual tanked volume by the pump gauge,.....
Ahhh now I understand. We have a lot in common, based on the fuel log numbers I have a sense as to where your +3 mpg comes from.

Much of my "city" driving is suburban and rural with many "beach runs" in the 35 - 45 mph range. But there are many hills to climb and descend in both directions, a 12 - 32 mph wind to contend with, and a fair share of miles in the gas guzzling 15 - 25 mph range. On the highway I drive at or just below 60 mph on the two lane, and at or just below 70 mph on the freeway. Judicious use of EV mode has been a difference that makes a difference in reaching my goal of 50 mpg overall.

I run 39 psi all around, no grill block or the other mods that help your numbers. I REALLY like your solar engine heating and will do something like that in the fall. Thanks very much :).

I reset the B counter / mpg gauge every morning and reset the A counter / mpg gauge at every fillup, enter and compare with the fuel log numbers.

I have the NAV trim package, and have noticed the miles traveled difference you've described. There are two reasons I trust the speedometer over the gps. First Honda has a government standard of accuracy to meet. Second the gps has to contact not less than 3 satellites, while accounting for the time the signal takes to get to and from the satellite. Then the gps must go through a sophisticated mathematical process to determine its location somewhere on the planet within x meters or feet from the actual location, Then the system has to go through the same process moments later to determine a second location within in x distance from actual, and finally compute distance traveled. Lots of room for error in all this vs a speedometer cables' direct connection to the vehicles' rotating wheels.

Thank you for your detailed and helpful reply above.
 

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I reset the B counter / mpg gauge every morning and reset the A counter / mpg gauge at every fillup, enter and compare with the fuel log numbers.
You know you can set your A counter to reset itself at every fillup? That's what I've done.
See the Trip A reset at refuel feature at pages 95 and 99 in the manual.
There are two reasons I trust the speedometer over the gps. First Honda has a government standard of accuracy to meet. Second the gps has to contact not less than 3 satellites, while accounting for the time the signal takes to get to and from the satellite. Then the gps must {basically calculate its &$$ off}.
Like Uriel said the (EDIT) European standard means speedo must read somewhere in between 0 and 10 % over the real speed. That is quite some margin.
I checked the odometer with the clock and speed, like you can if you drive 60 mph by GPS; then you will see one mile pass every 60 seconds exactly. If you do 60 by the speedo the time will run long.

Did the same for odo with the hectometer indications along the road here; every 100 meter the indications on the road pass synchronously with the number behind the point on the GPS odo. The car odo lags ever that little bit.

AFAICT the GPS readings are spot on; at least with my TomTom. The Honda navi might be less precise, though I'd be surprised.
My GPS and Google Maps also agree on the length of a route (driven vs. planned), usually to the decimal behind the point.
Thank you for your detailed and helpful reply above.
You're welcome and likewise :)
 

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Assuming you have sufficient visible satellites and are traveling in a straight line, the GPS should be very accurate for both speed and distance.

I'd just like to point out that the standard for speedometer accuracy is European and is locally adapted. The USA may have a different set of standards.

Sent from AutoGuide.com Free App
 

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I checked the odometer with the clock and speed, like you can if you drive 60 mph by GPS; then you will see one mile pass every 60 seconds exactly. If you do 60 by the speedo the time will run long.

Did the same for odo with the hectometer indications along the road here; every 100 meter the indications on the road pass synchronously with the number behind the point on the GPS odo. The car odo lags ever that little bit.
OK I'll check it and get back to ya.
 
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