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Discussion Starter #1
While trying to compare my mileage without CC vs with, I noted the following with CC off and watching the MID on trip B instantaneous and avg mpg meter. With 20 miles on the meter, the avg mpg was 46.4 mpg, and I was holding the instantaneous meter at 50 mpg. So, I'm expecting to see the avg start ticking up toward 50 mpg. After a few seconds, the avg dropped to 46.3. Odd, I thought. Another minute or so, instantaneous steady as a rock at 50, avg drops to 46.2. I swear I held the instantaneous at 50 while watching the average fall to 45.9 before I finally let instantaneous slip from 50. I can't explain this.

Has anyone else noticed something like this? Does anyone have an explanation?
 

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HI

I feel it's just a guide. Not really what you're getting for mileage. I did not reset the trip mileage this last tank and am not getting those wild mileage swings for the first few gallons like I do on a reset. I hold mine for extended times at 50 but can't seem to get over 43.9 this winter. looking forward to warmer weather for a mileage increase. No CC on my model. Were you going up a imperceptable grade at the time.(blue screen?)
 

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Freddy, thanks for the reply. I can't agree that it's just a guide. Gauges and displays should do what they purport to do; in this case, provide instantaneous and average fuel consumption. After a reset you should expect wild swings in your average, until you get several miles on the meter then it should settle down and change slowly. My assumption is if I reset trip B then that resets the average fuel consumption to zero. Then, as I drive the computer will periodically look at fuel consumed and miles on trip B and calculate the average fuel consumption. If this is true, then if I hold the instantaneous consumption constant at a higher value than the current average, then the average should begin to move up toward the higher instantaneous value. It should not matter whether I'm on a grade; I held instantaneous at a constant value, so average should be increasing, not decreasing. If this is incorrect, can someone tell me where I'm wrong. Otherwise I'm going to the dealer.
 

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Same boat

Actually, I've had exactly the same experience - keeping my instantaneous mileage well over my avg, yet seeing my avg drop.

I'm curious; have you learned anything from the dealer? My guess is that they don't have a lot of detailed knowledge about the car's software, but perhaps I'm wrong.
 

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Discussion Starter #6
Actually, I've had exactly the same experience - keeping my instantaneous mileage well over my avg, yet seeing my avg drop.

I'm curious; have you learned anything from the dealer? My guess is that they don't have a lot of detailed knowledge about the car's software, but perhaps I'm wrong.
cdaughton, thanks for the feedback. If its happened to someone else, then perhaps I'm not insane. Well, maybe I'm just a little insane. It hasn't recurred, and for my last 3 fillups the MID has been less than 5% different from calculated, so I'm not as concerned as I was right after I noticed the problem. I say all this to excuse the fact that I haven't gone to the dealer yet. I decided to wait for my first oil change. I'll update this thread when I know what they say, but I suspect you're right about the dealer's knowledge of the software, and this is probably a software issue.
 

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With 20 miles on the meter, the avg mpg was 46.4 mpg, and I was holding the instantaneous meter at 50 mpg. So, I'm expecting to see the avg start ticking up toward 50 mpg. After a few seconds, the avg dropped to 46.3. Odd, I thought. Another minute or so, instantaneous steady as a rock at 50, avg drops to 46.2. I swear I held the instantaneous at 50 while watching the average fall to 45.9 before I finally let instantaneous slip from 50. I can't explain this.

Has anyone else noticed something like this? Does anyone have an explanation?
I haven't noticed anything like this but it is an interesting question. Some factors to consider in searching for an explanation.

1. My understanding is that instantaneous mpg, with a reading of 50, is 'actually' somewhere between 45 and 50.

2. The average is recomputed every ? period of time. I think its every minute.

3. It could be that prior to the reduction in the average from 46.4 to 45.9 there were periods of very low instantaneous mpg (due to acceleration) and a period of very high instantaneous mpg (battery only EV mode which is reported as 150 average mpg). If so, the initial 46.4 is a false high that reflects the computer software's poor ability to accurately measure mpg while in EV mode. Some additional miles would be needed to average out these extremes of instantaneous mpg.

4. I have repeatedly found that the MID is more optimistic of actual mpg, when the tankful being measured included lots and lots of EV mode driving. I talked with the dealer last year, and sent a complaint to Honda's USA HQ. As far as I know, no software fix has been made.
 

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Discussion Starter #8
I haven't noticed anything like this but it is an interesting question. Some factors to consider in searching for an explanation.

1. My understanding is that instantaneous mpg, with a reading of 50, is 'actually' somewhere between 45 and 50.

2. The average is recomputed every ? period of time. I think its every minute.

3. It could be that prior to the reduction in the average from 46.4 to 45.9 there were periods of very low instantaneous mpg (due to acceleration) and a period of very high instantaneous mpg (battery only EV mode which is reported as 150 average mpg). If so, the initial 46.4 is a false high that reflects the computer software's poor ability to accurately measure mpg while in EV mode. Some additional miles would be needed to average out these extremes of instantaneous mpg.

4. I have repeatedly found that the MID is more optimistic of actual mpg, when the tankful being measured included lots and lots of EV mode driving. I talked with the dealer last year, and sent a complaint to Honda's USA HQ. As far as I know, no software fix has been made.
Moviemike, thanks for your input. It seems to me that for an indicator calibrated in increments of 5mpg that a reading of 50 should indicate an actual value from 47.5 to 52.5, but I don't know what the meter actually does. It has occurred to me that if the avg reading is based in part on a predictive algorithm that could explain what happened. But that sounds overly complex. I would love to know how it really works.
 

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mpg

What is this EV mode I keep reading? Our Insights do not have an EV mode. The electric motor is used for torque and/or acceleration only.
It has engine shut off mode but thats not EV.
 

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Freddy, I beg to differ about the EV mode. Page 84 of the manual shows a mode where only the IMA motor is powering the vehicle. If only the electric system is providing power, then that is an EV mode. Granted, it is computer selected; the driver cannot press an EV button, but you can drive in such a way that the computer will select EV. I do it frequently, just to see how long I can make it last.
 

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I never received a manual with my car so I am unaware of pg 84. But I will look it up Thank You. I'm just basing it on my experience driving the car. I don't consider coasting down a hill with the fuel injectors off and the engine spinning providing elec power for steering and fans EV mode. To me EV mode is starting from stop on battery only and moving a distance before the gas engine kicks on. This car doesn't do that. Don't take it the wrong way I like this little car immensely and am glad I bought it. I look forward to driving it. Especially now that wall st is driving gas prices up. Again.!
 

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You are right -- the car will not start from stop on battery, but it will go into battery power only at low speed, meaning the ICE is off and the IMA motor is pushing the car. Tricky to get into that mode, and even trickier to maintain it for very long, but it will do it. By the way, I LOVE the gas mileage, also. Got my flower today at 2810 miles, and got 58.1mpg on my 27 mile commute this afternoon. Woo Hoo!
 

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Moviemike, thanks for your input. It seems to me that for an indicator calibrated in increments of 5mpg that a reading of 50 should indicate an actual value from 47.5 to 52.5, but I don't know what the meter actually does. It has occurred to me that if the avg reading is based in part on a predictive algorithm that could explain what happened. But that sounds overly complex. I would love to know how it really works.
Me too !

An interesting experiment I tried, was to drive on a flat road at a steady speed (near 60 mph), but most importantly at a steady 50 mpg on the instantaneous mpg readout (I call it the "slider"). I then zeroed the avg. mpg, and ran for a couple minutes to see what avg. figure would appear while the slider was holding at 50. I did it 3 times. Each time the avg. figure was a little less than 50?

Freddy:
An easy way to know when the car is in what I call "EV mode" is to look at the energy flow screen on the MID. This is the screen with the arrows that go to and from the car, battery, and gasoline nozzle icon. When the nozzle icon is dark and an arrow appears from the battery pointing toward the car, only battery power is being used to power the car. I call this ev mode.

The Insights' hybird system, an Integrated Motor Assist system (IMA), is of a different design than the Prius system you referred to. The IMA applies electric power to directly turn the engine's crank shaft. Thus the system aids the little engine for "high" power needs such as standing start acceleration, passing, or hill climbing. With the fuel cut off engaged while coasting, one can gently press the gas pedal and engage battery power only (ev mode) and obtain enough power to prevent the car from lossing much speed. Further pressing of the gas pedal will make the engine turn on for additional power to accelerate or maintain speed.

The Prius system gets its best mgp at very low speeds - say 10-20 mph. The Insight's best is in the 35-50 mph range. making the Prius ideal for driving in older East coast cities such as Boston. The Insight will do best in rural or suburban areas such as Los Angeles.
 

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Is EV mode affected by ambient temperature?

Keeping with the EV mode (IMA only, that is): is it safe to assume that, like the auto stop/start, it is affected by the ambient temperature? I've owned my Insight for only a couple weeks and the weather has been pretty cold, so I frequently cannot auto stop/start until after I've been driving for 15-20 minutes.

On the colder days, I've also had very little luck getting into EV mode, which seemed quite easy on one of the warmer days we've had.

I assume this is a function of ambient temp, coolant temp and (obviously!) battery charge level, but does anybody have any additional information?

Thanks!
 

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.......I assume this is a function of ambient temp, coolant temp and (obviously!) battery charge level, but does anybody have any additional information?
Perhaps also ECON button on (leading to an increased "affinity" for auto/stop) and climate control system "off" (shorter duration of auto/stop when on).

An interesting experiment might be; In cold outside temperatures, with engine cold light off, heater / climate system off, and battery at charge level 5 or 6(level 6 is maxium or fully charged), see if entry / duration of ev mode is similar to warmer weather operation?
 

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O.K. I changed the screen and saw the ev mode. I guess it's nice but I'm still unimpressed. I've owned cars without power steering and would put them in neutral and shut the engine off and see how far I can coast and get similiar results without a computer doing it for me.
 

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I can't agree that it's just a guide. Gauges and displays should do what they purport to do; in this case, provide instantaneous and average fuel consumption.
My 2 bits.

No gauge or display is 100% accurate ... even if you buy a $1 Million volt meter ... there is always a margin of error.

Margins of error vary with conditions ... rate of flow , vehicle speed, temperature, RPMs , atmospheric pressure , etc. ... etc...

Also keep in mind ... what is actually put in the car ... unless you have quantified the volume of gasoline put into the car ... if there is an error ... you don't know how much is the car and how much was the pump.

There will be a sticker on the pump for the last time it was inspected ... on that date when tested the pump had to meet your state standards ... it can have changed between then and now.

even if you assume it hasn't changed ... what was the acceptable margin of error at that time? ... have you checked with your state department of weights and measures to know what their testing methods and requirements are?

If you want to know how much was put in the car accurately measure it yourself , with a method you know what the % of error rate is under the conditions you are measuring it.... then drive a distance you know the distance of ( mile markers ) etc ... GPS and dash distance gauges and meters are not 100% accurate either... take into account the known % of error.
 

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O.K. I changed the screen and saw the ev mode. I guess it's nice but I'm still unimpressed. I've owned cars without power steering and would put them in neutral and shut the engine off and see how far I can coast and get similiar results without a computer doing it for me.
Hi, freddy - I may well have misinterpreted your note, so I apologize in advance if I have done so.

I'm not really sure that what you've described is the Insight's ev mode, so much as just coasting. As amorris mentioned a little earlier, it can be a little tricky to really get into ev mode. When you are there, though, you aren't doing the equivalent of coasting with the engine off (I made quite a habit of doing that with my last car, too).

Instead, you are actually driving the car on battery only. As far as I have been able to tell, you should be able to sustain your current speed on flats, sometimes for a while, without firing the gasoline engine back up. Now, it takes a pretty light touch with the throttle, and I am not able to consistently do it, especially if it's not a warm day. Once you get into ev mode, though, you can definitely cruise on battery only.
 

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It takes a bit more intuition to drive the Insight than other hybrids. I have about 1/4 mile strait flat drive into my apartment complex that has speed bumps every 70 feet or so. If I get it just right, I can coast the whole way using just the electric motor.

I noticed the gas will kick back on if I get below 10 mph, so I will just coast at a constant 11-13 mph while my readout is maxed at 100.

I notice that all the IMA does at these speeds is decrease engine drag so you can coast longer, it is the equivilant to pushing the clutch for manual transmissions.
 
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