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Unbelievable but true...

In mixed city and highway driving
Had we relied on the onboard computers, the Prius would have won by a landslide, as by the end of the trip they read 57mpg and 42mpg for the Prius and Jeep respectively.

However, to get the real figure, we calculated consumption based on how much fuel each car had used over the 160 miles. The result was astonishing: both cars had used nearly identical amounts of fuel. The Jeep had averaged 38.9 mpg - only 3.1 mpg less than its computer had recorded. However, the computer of the Prius appeared to be telling whoppers: it actually achieved just 39.9 mpg - a massive 17.1 mpg less than it had claimed.
That's UK gallons and the diesel is not sold in the US.

http://fifthgear.five.tv/jsp/5gmain.jsp?lnk=601&featureid=1196&pageid=-1
 

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I've heard similiar stories on the Prius. Just goes to show you, even when you go green, you can't trust your DIC.....
 

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Unbelievable but true...

In mixed city and highway driving
Had we relied on the onboard computers, the Prius would have won by a landslide, as by the end of the trip they read 57mpg and 42mpg for the Prius and Jeep respectively.

However, to get the real figure, we calculated consumption based on how much fuel each car had used over the 160 miles. The result was astonishing: both cars had used nearly identical amounts of fuel. The Jeep had averaged 38.9 mpg - only 3.1 mpg less than its computer had recorded. However, the computer of the Prius appeared to be telling whoppers: it actually achieved just 39.9 mpg - a massive 17.1 mpg less than it had claimed.
The highlighted part is the truly unbelievable part.

Keeping in mind we need more detailed in formation here............. there could be some bladder expansion issue at work in the above.............

IMO, 80 -95% plus of the individually reported and inexcusably, - the 'Press' reported mileage figures are wrong - way overstated for many years worth of Honda and Toyota 'high mileage' oriented hybrids.

Many rely on the computer and the Prius fuel bladder with all its functional shortcomings makes filling and measuring accurately very difficult - which 'tends' to net optimistic numbers as well although not always - it can go the otherway as well.

IMO, Its a scam thats gotten Honda into a class action lawsuit that was originally going to include Toyota for primarily the Prius.

My understanding ( from over a year or two - or more ago ) is that they ( Toyota ) developed a magic complaint procedure - dialogue to avoid inclusion - thats old info so don't know where things are now.

Notice how once again, our press, and not just the automotive corps - doesn't cover this timely issue. Total FAIL.

If this was GM and Ford it wouldn't happen this way.

The best recent example of this kinda' media crap is the recent Leftlane News 'advertorial' for the below Edsel - reigning sales disaster champion ie the Lexus LS600h L.

Compare their 'observed' fuel economy versus any of the others in the UK, Europe, and even here with Motortrend.

The net average onboard reporting error for Honda and Toyota hybrids - so affected - we must say that because one would think at some point this had to be 'adjusted' - then again maybe not or maybe only 'partially' - is in the realm of 15 -20% although it can be much higher for shorter periods of time.

Some would say its in the realm of 15-25% - with a max of about 40 - 45% - seems to be dependent on environmental conditions Xs duty cycle.

Year, make, and model does/may matter as well - its not exactly clear.

In two senses its an erratic type of error - it doesn't happen all the time nor the same way when it does - and the amount of error both percentage wise and in terms of the ordinal amount appears to float around a bit as well.

Interestingly enough, Toyotas and Hondas on board systems never seem to have been reported as reading low. :lmao::lmao:

Also of interest - the more performance oriented models from both appear to net less error - the discontinued Accord Hybrid probably was best with the least amount of error % wise.

Remind yourself of why that one failed in the market place ......................

Fords and GMs don't seem to do this - if anything some of GM's (BAS) appear to read low.
 

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What is the real deal with the Prius? What are the real world MPG numbers? I have heard so many conflicting reports, but if the Prius really only get 40mpg average what is the point:confused:
 

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What is the real deal with the Prius? What are the real world MPG numbers? I have heard so many conflicting reports, but if the Prius really only get 40mpg average what is the point:confused:
Hybrid systems are so unpredictable that you really can't get a definite average. Plus, it depends on the way the car's driven. Some drivers get 50+ MPG with the prius, but I've heard that others are getting only 35 MPG with it.
 

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And why can't GM do this with Hummer? Once again GM will be playing catch-up. :-(
 

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What is the real deal with the Prius? What are the real world MPG numbers? I have heard so many conflicting reports, but if the Prius really only get 40mpg average what is the point:confused:
Thats a really tough number to pin down accurately.

Anybody on either side of it that tells you differently is blowing at least a large amount of smoke.

As far as the actual real world 'total user fleet' numbers go, I wonder if anyone really knows for sure, including Toyota.

Its not just the issues raised above - its also because Prius/HSD is extremely sensitive to how you use it and simultaniously - environmental conditions in general .

In a wide range four season environment ie lots of hot and lots of cold the resulting swings are huge and are hugely different than a gasser.

All the factors in those two groups outside the revised 2008 EPA 'method' work to lower the actual results - as they do for gassers in general ( diesels are a different story although somewhat similiar ) but the critical difference is the HSDs are way more affected - and its almost all to the negative side of things in a big way.

Then you have the hypermiler 'effect' on the overall numbers base.

There maybe more to that than meets the eye as well. :)

Bottomline; tough to say - with a wider range between high and low real numbers whatever they are.

Very situationally dependent.

Overall, overstated as far as total population goes.

The phrase " Your mileage may vary " has never been so true and so strongly APPLICABLE as it is in regards to Toyota's HSD.
 

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38.9 mpg? That's nothing. I recently heard about this guy that bought a Chevy 4x4 and got 87 mpg. Then GM came and wanted it back, because it was a secret truck worth $400,000.
 

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What is the real deal with the Prius? What are the real world MPG numbers? I have heard so many conflicting reports, but if the Prius really only get 40mpg average what is the point:confused:
Forget the euro numbers.. different units / different biases.

For the US here are the two sites with definitive real world numbers..

The EPA site itself... www.fueleconomy.gov search for real world reports for different model years

www.GreenHybrid.com has a database covering all the hybrids on the road now.

Both sites come up with the same number for combined driving @ ~ 47.5 mpg
 

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Hybrid systems are so unpredictable that you really can't get a definite average. Plus, it depends on the way the car's driven. Some drivers get 50+ MPG with the prius, but I've heard that others are getting only 35 MPG with it.
There is definitely a learning curve to get the best out of any of the hybrid. It only takes about 2 weeks of common sense driving and some initial guidance by someone who know what the vehicles can do.

One of the principals at GreenHybrid.com was given one of the first prototype Yukon 2-Modes to test for a day or so last winter and got 28-30 mpg!!!!!!!

Getting 50 mpg on a Prius in moderate weather is a snap. Getting 60 mpg is difficult without some really special effort. Getting 35 mpg is almost impossible without trying. But knowledge is everything.

Ditto the Civic. It's very very hard to get 60-ish mpg but 45-50 is easy. 35 mpg is hard to do without trying to get bad fuel economy.

All the hybrids on the road now, and in the future, do what they're supposed to do just as the new diesels do. Getting bad fuel economy means very unusual bad circumstances or trying to get bad results.
 

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38.9 mpg? That's nothing. I recently heard about this guy that bought a Chevy 4x4 and got 87 mpg. Then GM came and wanted it back, because it was a secret truck worth $400,000.
Yea and my grandfather has a friend who knows someone who accidentally got a Ford that got 150 mpg or something...and Ford came and wanted it back..but he said no and put it on all his new cars.

As if these secret cars are on the same line and could make it to a dealership...and then get sold before anyone notices...
 

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Anyone else find it funny that with all the computers on board etc etc you still can't beat filling up the tank, and taking the number of miles driven/number of gallons used?

Not sure how true it is, but there is the statement that has been around for many years about NASA spending millions to develop a pen that can write in space, the Russians used a pencil.
 

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I wonder what VCDJ has to say about this? His beloved Prius getting crappy mileage! Any body want to make a guess?
 

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Forget the euro numbers.. different units / different biases.

For the US here are the two sites with definitive real world numbers..

The EPA site itself... www.fueleconomy.gov search for real world reports for different model years

www.GreenHybrid.com has a database covering all the hybrids on the road now.

Both sites come up with the same number for combined driving @ ~ 47.5 mpg

Thanks--good site! Has some interestring real world numbers
 

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Discussion Starter · #16 ·
There is definitely a learning curve to get the best out of any of the hybrid. It only takes about 2 weeks of common sense driving and some initial guidance by someone who know what the vehicles can do.

One of the principals at GreenHybrid.com was given one of the first prototype Yukon 2-Modes to test for a day or so last winter and got 28-30 mpg!!!!!!!

Getting 50 mpg on a Prius in moderate weather is a snap. Getting 60 mpg is difficult without some really special effort. Getting 35 mpg is almost impossible without trying. But knowledge is everything.

Ditto the Civic. It's very very hard to get 60-ish mpg but 45-50 is easy. 35 mpg is hard to do without trying to get bad fuel economy.

All the hybrids on the road now, and in the future, do what they're supposed to do just as the new diesels do. Getting bad fuel economy means very unusual bad circumstances or trying to get bad results.
If you attach a couple of horses to a Prius you can get infinite MPG.
 

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38.9 mpg? That's nothing. I recently heard about this guy that bought a Chevy 4x4 and got 87 mpg. Then GM came and wanted it back, because it was a secret truck worth $400,000.
Didn't that truck have the 100mpg carburetor that has been rumored to have existed for years, but supposedly was kept secret because of a oil company/GM conspiracy? :rotf:
 

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I wonder what VCDJ has to say about this? His beloved Prius getting crappy mileage! Any body want to make a guess?
Didn't you hear that 'whoomp'? His head imploded. (As opposed to exploded, since a vacuum cannot expand :D )
 

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Anyone else find it funny that with all the computers on board etc etc you still can't beat filling up the tank, and taking the number of miles driven/number of gallons used?

Not sure how true it is, but there is the statement that has been around for many years about NASA spending millions to develop a pen that can write in space, the Russians used a pencil.
http://history.nasa.gov/spacepen.html

There was a show on discovery channel I think called Factory Made or something. They had these pens on during an episode I saw part of.
 
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