Faking the Milage?

[DavidChandler]

After repairs from an accident our Prius milage dropped from the high 40s (on long trips) to the high 30's (for the same trip). Also our daily milage was similarly reduced. When I took it back to a dealer for diagnostics (approved by my insurance), the dealer gave it a clean bill of health and claimed over 60 mi/gal on short trips and high 50s on a trip over 100 miles (which they called and got permission to conduct). Driving it off the lot I was NEVER able to get it into that range no matter how conservatively I drove. Now my insurance is balking on paying for the diagnostics. My question is whether it is technically possible for the tech at the dealership to feed in a false reading to the computer? Apart from direct intervention in the computer, is there some special driving technique that could boost the milage in this way? I can't get anywhere near those results (apart from coasting one-way down a long hill).

[brick]

Anything is possible. Did you actually see that mileage displayed on the MFD? If not, the simpler explanation is that they looked for codes, drove it around, saw nothing that they could really fix and then told you whatever would make you go away. The other possibility is that the tech really did get mileage that high mileage somehow. There are techniques that can get a Prius comfortably over 100mpg under perfectly ideal conditions, but I really doubt that he would go to the trouble to do that.

What was affected by the accident? How long have you had the car back and how many miles have you driven? Does it drive ok other than the mileage? If I could check one mechanical parameter it would be the alignment. A bad alignment can cause all kinds of extra drag, not to mention rapid tire wear. And I would definitely make sure that the basic stuff is set up right: tire pressure, A/C not on all the time, etc.

[berylrb]

<div class='quotetop'>QUOTE(DavidChandler @ Jan 10 2007, 06:49 AM) [snapback]373528[/snapback]</div>

... the dealer gave it a clean bill of health and claimed over 60 mi/gal on short trips and high 50s on a trip over 100 miles (which they called and got permission to conduct). ...[/b]

Like Brick suggested the real tale all would have bee the MFD. But even with a reset, if you're still on the same tank, go on and fill up and see what the mi/gal is? Assuming you fill up the same, clicks no-clicks, slow setting on the pump, temp, etc., you should get some discernible boost you'd think for 100 miles plus of dealer driven 50-60 mpg, eh?

Another more plausible possibility, giving the dealer the benefit of the doubt, they simply saw "bars" of 50 mpg on the 100 mile trip, and "bars" of 60 mpg on short trips.

[dcoyne78]

Depending on how you drive and where you drive, it is definitely possible to get those kinds of numbers, or even much better in a Prius.
Last summer I was routinely getting tanks in the 60s and even a few in the 70s, with my best over 80. Also check out VaBeachPrius on the green hybrid or cleanmpg database, he is doing much better than I am in this regard. There are also some great trips over at cleanmpg on pulse and glide in a Prius. Good luck.

Dennis

[galaxee]

if it was on the mfd, it was real.

frankly if they were talking about the bars i wanna know how they got that first 5-min bar over 30 mpg because i rarely if ever see that.

there are lots of techniques to boost your mileage. search for "why don't i get the EPA mileage?" in the article system.

could be that the ecu's were going through the re-learning process if they were reset.

[hill]

<div class='quotetop'>QUOTE(DavidChandler @ Jan 10 2007, 07:49 AM) [snapback]373528[/snapback]</div>

After repairs from an accident our Prius milage dropped from the high 40s (on long trips) to the high 30's (for the same trip). Also our daily milage was similarly reduced.
. . . . .
. . . .
Apart from direct intervention in the computer, is there some special driving technique that could boost the milage in this way? I can't get anywhere near those results (apart from coasting one-way down a long hill).
[/b]

YES, there IS some special technique. It's called P-R-A-C-T-I-C-E. Search the site here. You'll find that (I think it was) Evan started a "POST YOUR BEST MILEAGE" thread. Plenty of us here on PriusChat regularly BEAT the EPA's ratings, doing better than 60mpg. I think my best was 61.7mpg or so, with mileage being over 610 on a single tank. A couple of obsessive folks here have even gotten over 70mpg ... and I remember one person here showing his MFD reading over 800 on a single tank. If that doesn't friek you out enough, the GuinessBook is over a THOUSAND on a single tank. But you gotta be willing to drive like a dork. The tech may drive a Prius, and if so, he too, knows what to do. So read up on pulse & glide - and other such dork techniques, and YOU TOO can join us in the crazy land of dorkie-dum. :^)
And welcome to priuschat, too, BTW.

[kettledrum]

<div class='quotetop'>QUOTE(DavidChandler @ Jan 10 2007, 06:49 AM) [snapback]373528[/snapback]</div>

After repairs from an accident our Prius milage dropped from the high 40s (on long trips) to the high 30's (for the same trip). [/b]

This seems to be the key of the question. P-R-A-C-T-I-C-E is not the problem, but it could be any number of things. My ignorant 1st guess would be temperature, and tire pressure?

[hill]

<div class='quotetop'>QUOTE(kettledrum @ Jan 10 2007, 01:51 PM) [snapback]373636[/snapback]</div>

This seems to be the key of the question. P-R-A-C-T-I-C-E is not the problem, but it could be any number of things. My ignorant 1st guess would be temperature, and tire pressure?
[/b]

Well, no need to point the finger of ignorance, but you're right. Too many unknowns ... to say whether it's temps versus P-R-A-C-T-I-C-E. I shouldn't have presumed that since they only have ONE post, that this meant they may have only driven a few hundred miles. But being ignorant of the facts, I wouldn't rule that out so quick.

[Tom_06]

<div class='quotetop'>QUOTE(galaxee @ Jan 10 2007, 11:28 AM) [snapback]373591[/snapback]</div>

if it was on the mfd, it was real.

frankly if they were talking about the bars i wanna know how they got that first 5-min bar over 30 mpg because i rarely if ever see that.

[/b]

I'd guess they warmed the car up, started driving, then reset the consumption screen manually. That way the first bar and all following would indicate what the car could do in city or highway driving, whichever they were testing. I think for a service person checking the car for mileage problems that would be both fair and closer to EPA technique.

- Tom

[kettledrum]

<div class='quotetop'>QUOTE(hill @ Jan 10 2007, 05:04 PM) [snapback]373810[/snapback]</div>

Well, no need to point the finger of ignorance[/b]

Sorry, not wanting to point fingers....I just didn't want to discourage a newbie so quickly. I know I would be discouraged if I was the OP and told I needed to practice more after saying I used to get X but are now getting Y mpg.