[Ttam]

Is there a display in the 2004 Prius that shows lifetime MPG? I know about the consumption screen, and have been resetting that at every fillup.

- Ttam

 

[jeff_kash]

Mine resets after every fill-up as well. You have to keep lifetime mpg the old-fashioned; you have to add and divide.

Jeff

 

[mrv]

classic Prius: either NEVER touch the Reset button on the Consumption Screen, or else keep records of how much gasoline you have filled the car with.
2004 Prius: you have to manually keep records of how much gas you have put in, as the car automatically resets the Consumption Screen at each fillup.

sadly, the Prius does not have a lifetime MPG meter like the Hondas do.

 

[BIF]

If I may add an observation:

Lifetime MPG may or may not be useful beyond your own curiosity. Why, you may ask?

Have you ever bowled in a bowling league or a golf league? Remember how easy it is to improve (or damage) your average at the beginning of the season? And how difficult it is to make it change much by the end of the season?

You will notice the same thing if you're keeping track of your car's lifetime MPG. After 10 or 20 tanks or so, it will be difficult or even nearly impossible to budge that lifetime MPG one tank at a time. Only by modifying your driving over the NEXT 10 or 20 tanks, could you stand a chance to modify the LMPG.

Likewise, when your car is 4 years old, it may take another 3, 4, or more years for you to notice a marked difference in your LMPG, even if you have turned over a new leaf, and are driving much more conservatively.

Hence, my opinion that over-reliance on your LMPG might be not as useful as you might think, and it may even set you up for frustration over time.

On the other hand, I believe that tracking my MPG tank by tank, week by week, or even month-by-month is far more useful. If I have the car long enough, I'd be able to compare June '05 or June '06 with all prior June MPGs, to see my summertime driving trends. I think this would be much more useful to me in terms of behavior modification and self-improvement.

Of course, I'll probably use a spreadsheet or the mileage database on greenhybrid.com, so my LMPG will probably be tracked anyhow...but it will become less and less useful over time, until a point comes at which I'll just ignore it entirely, because it won't change a lot from tank to tank.

Did I make any sense at all?

 

[john1701a]

Just look at the 59,827 miles of data for my 2001 Prius. The LMPG value rarely ever changed after awhile.

As impressive as the number would be to show off to others with, that lack of change would eventually drive the typical person crazy... especially when you realize it isn't totally accurate anyway (rounding errors & finite measurement impossibility).

The do-it-yourself method is only way to get LMPG. And that way, you can enjoy watching it go up & down (while learning as you go) while the real-world conditions toy with your Prius.

 

[john1701a]

Since neither the Toyota MD nor the Honda FCD is dead-on, the value of LMPG becomes completely WORTHLESS after awhile.

Think about it.

The third year of ownership for my 2001 Prius (starting with the odomoter at 38,486 miles and going to 57,802 miles) resulted in a calculated Lifetime value shift from 44.7 MPG to 45.3 MPG.

That shift of only 0.6 MPG is actually less than the margin-of-error, which for my 2001 Prius was 2.1 MPG. So... the shift is so small, you can't even officially count it!

The benefit of calculating the value yourself should be obvious.

 

[Guest]

Hi John1701a:

___A LMPG meter is not useless by any stretch In the Honda Insights, there are Trip A and B, Segment, and LMPG readouts over the distances selected along with Instantaneous Fuel Consumption on all screens if you choose to view any or all of the information available. All are very useful.

___Here is just one use for the lmpg Lets say you were looking for a used HCH or Insight. One HCH has a lmpg showing 26 mpg over 43,000 miles as displayed on the lmpg and odometer screen and another has a lmpg of 44 mpg over 46,000 miles. What does the lmpg tell you about how each car was driven and which would you rather purchase? In the case of an Insight, would you rather purchase one w/ a lmpg of 84 mpg or one w/ a lmpg of 52 mpg? It is a great sales as well as benchmarking tool. Just last week I was at the GreenHybrid.com group meet at Miller Park in Milwaukee and a fellow Insighter probably didnt believe me but took a quick look through my FCD screens (FCD = Fuel Consumption Display) just to see the LMPG at 82.2 mpg, my 60 + mile segment showing > 91 mpg, and my then current tank at ~ 92 mpg and a touch below 1,200 miles range. Without the lmpg and other displays, all I may have been doing is mouthing hot air.

___As for accuracy, my last fillup after 14,981 miles showed the LMPG at 82.2 mpg and the actual calculated at 82.31336772 mpg. Even Greenhybrids Real Hybrid Mileage Database cant keep up to this accuracy because Jason hasnt programmed the distance to any decimal points nor the FE to anything over 1 place on tank over tank averages! The LMPG, Segment, and Trip A/Trip B meters in a Honda Hybrid measure off the same inputs for all of the data screens giving instantaneous fuel economy as well as accumulated fuel economy over the varying distances as you would like to view.

___The benefit of seeing the lmpg with a glance at the odometer screen should be obvious. No calculating and it is always visible.

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:xhn8y17e][email protected][/email:xhn8y17e]

 

[Daniel]

... As for accuracy, my last fillup after 14,981 miles showed the LMPG at 82.2 mpg and the actual calculated at 82.31336772 mpg. Even Greenhybrids Real Hybrid Mileage Database cant keep up to this accuracy ...

You are confusing accuracy with precision. A high degree of precision is meaningless without corresponding accuracy. The accuracy is limited by the error inherent in the measurements. Even the second decimal point is highly inaccurate on both miles driven and gas pumped, which means that anything beyond one decimal point of precision is meaningless, useless, and silly.

However, I agree that LMPG would be useful information to the buyer of a used car, as it would serve as an indication of the driving habits of the previous owner(s).

 

[Guest]

Hi Daniel:

___The key here is that after 14,891 miles, the lmpg showed 82.2 mpg and the actual calculated was 82.31336772 given 3 digits to the right of the decimal point for gallons purchased at the stations I use and just 1 digit to the right of the decimal point for distance from the odometer. I dont think you nor do I care that Excel defaulted to 8 decimal places but I believe both of us care that the lmpg matches the calculated quite well. As was stated above, Since neither the Toyota MD nor the Honda FCD is dead-on, the value of LMPG becomes completely WORTHLESS after awhile, is not the case from my short time behind the windscreen of a Hybrid?

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[emaile2b57cl][email protected][/emaile2b57cl]

 

[john1701a]

Since the margin-of-error is not constant nor even close on average, you can't assume the value displayed is even remotely accurate. So the best you can say is "within a few MPG". And since real-world vehicles (not the extreme example Wayne continues to push) will all be pretty much the same.

There is also no way you can possibly know how a LMPG was achieved. So there isn't even any real useful benefit for someone interested in buying the car used. In fact, there is nearly a 100 percent chance they won't be able to get the same value. Driver habits alone have a profound effect on performance. So the LMPG only hints at what might be possible.

As for an entertainment aspect after 20,000 miles, there isn't one. The value on a hybrid getting 50 MPG will only change 0.1 every thousand miles.

 

[Daniel]

... There is also no way you can possibly know how a LMPG was achieved. So there isn't even any real useful benefit for someone interested in buying the car used...

Agreed that someone else's mpg may not be repeatable by a new owner. But is there a way to get exceptionally good mpg using driving habits that would be bad for the car? My idea is that higher than average LMPG would indicate that the car has been driven gently, and is therefore likely to be in better condition than a car with average or below-average LMPG.

 

[BIF]

Agreed, Daniel, but as the car ages and goes through several owners, the LMPG figure will be even less important than it already is not.

And LMPG will not tell accurately or reliably much about "how the car was driven" if the car was family-owned and driven by more than one person.

Furthermore, a "gentle driver" is not necessarily the same thing as a "good caretaker" of a car.

I've known many gentle drivers who never did oil changes, only did tuneups after the car started having problems, and only changed tail lights when they got pulled over by the police. Conversely, I've known lots of "active" drivers who are very attentive, keeping up with their oil changes and tuneups, and replacing wear-and-tear items long before they wear out. I fit into the latter classification quite nicely.

 

[Guest]

Hi Bif:

___In terms of taking care of the automobile and the LMPG, if there is more then one driver and one is getting 80 + and one is receiving 30 +, the lmpg wont be 80 As for maintenance records and such, I dont know many that cannot provide them anymore either. Just look up a VIN at your local Honda or Toyota dealer for any and all services performed on any Honda or Toyota in the country!

___When I purchased my own Insight, the lmpg was at 80.2, the service records for everything were in front of me, and the automobile was Honda certified w/ a 7 Yr./100,000 power train and extended bumper to bumper for 1 year/12,000. I dont know how much more of a cream puff I could have asked for nor purchased. I even spoke with the original one owner which is also easy to track via CarFax and I had in my hand as well! Now take a look at the an older Prius w/out a lmpg display up on E-Bay. The Insights with lmpgs of 40 - 60 mpg are glowing examples of how the automobile was treated irregardless if it was taken care of to the letter of the manual or not. Show me the receipts is all that needs to be asked and the lmpg will tell you the rest.

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:13x4hax2][email protected][/email:13x4hax2]

 

[greenhybrid]

Let me add here that it really doesn't matter if the GreenHybrid database allows for 1 or 2 or 3 decimal places for input. The fact of the matter is that the car can't be that accurate anyway, or the fuel pump while we're at it! But, should you doubt even this, by having 1 decimal place there will be at most a .05 MPG error (excluding error by the display) due to economy values. Am I right?

I think the bigger concern is the actual distance covered. Should someone drive a 3.4 mile tank at 50.1 MPG and then a 3.5 mile tank at 100.5 MPG, the average will be way off. Why? Because tanks are usually measured in whole numbers and since rounding takes place on the odometer, it's likely to cause a larger discrepency. It will turn into 3 miles and 4 miles. This is exaggerated, of course, because the likelyhood of a 3 mile tank is close to impossible.

 

[john1701a]

> Insights with lmpgs of 40 - 60 mpg are glowing examples of how the automobile was treated irregardless if it was taken care of to the letter of the manual or not.

So... you consider "treated" as the way the person drives, where low MPG means they abused the car?

Not everyone that owns an Insight cruises on highways for lengthy periods. As a result, the city & burb driving can kill their LMPG. That doesn't mean they did anything to harm the car.

The same goes for Prius. Low LMPG is not necessarily a bad thing. So "glowing" doesn't apply.

 

[Guest]

Hi John1701a:

___You bet I do. Would you rather purchase the same automobile with a lmpg of 80, 60, or 40? An all highway driver would definitely be the better purchase. An all highway or city that has been abused showing far below EPA estimates would be suspect at best and a disastrously poor purchase at its worst. I wish all automobiles had a lmpg readout but that is just me.

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:3egqz690][email protected][/email:3egqz690]

 

[john1701a]

I would be suspicious of an above-average LMPG.

 

[BIF]

And a brief word about maintenance: A lot of people do their own maintenance. I used to do all of mine on my Trans Am and my Miata.

These would have no history with Toyota or Honda.

And when you sell or trade the car to a dealer, nobody wants your maintenance records. This happened to me both times, when I sold my Corvette and a year later, my Z3, to Carmax. No sir, we don't need any maintenance recoreds.

So it's possible that a perfectly good, well-maintained car would have "no" history records.

 

[Guest]

Hi All:

___Here is the direct example

___Which would you rather purchase? This Insight being auctioned off w/ a lmpg of just 41.5 mpg can be seen over on Ebay, here.

___I combined a pic of my own gauge cluster I snapped off 20 minutes ago w/ that from the auction linked above These 2 pictures should speak volumes as to how one Insight was driven vs. how the other is driven and should weigh heavily on which Insight someone might purchase if they were looking at these 2 Insights in particular? Pretty strident comparison and it makes the case to have a lmpg meter in all vehicles

___Bif, this might help you out with your brand new Package 9. I used to do my own oil and filter changes, tranny flushes, coolant swaps, etc. until I found out my local Honda dealer changes oil and filters on the Insight for just $9.63. I hand them 3 Qts. of Mobil1 0W-20 Tri-Syn and a Walmart purchased SuperTech filter and they do the rest including handing me back the extra qt. for the next change. They now change the MDX, Corolla, and Ranger as well given the price.

___Other Maintenance, TSBs, Recalls, Repairs, and Oil and Filter changes, etc. are listed in Hondas database for the Insight currently. If the owner decides never to have his Honda/Toyota/Ford/Chevrolet or whatever serviced at the dealership, then all you would have is faith. If purchased PP, you could ask for the service records and most local shops now track everything they do. At least with a LMPG meter, you do have some idea as to how it was driven hopefully.

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:2mikxxjb][email protected][/email:2mikxxjb]

 

[john1701a]

The original question centered around the ON-GOING ability for an owner to monitor Lifetime MPG, not the flash-in-the-pan usefulness for selling the car.

This graph showing the 3 years of data from my 2001 Prius clearly shows there isn't any after awhile, that the value changing slows to a crawl.

What's the fun in that?