10K MPG Check: Not impressed

[Blind Guy]

Originally Posted by Coastie

Passed the 10k point a few days ago. So far, the MPG is essentially the same as what my Gen II Prius gets (2004 with 103k miles).
Here's the data:
1. The trip ODO average MPG for the 10,000 miles= 46.4
2. Actual computation of MPG for the 10,000 miles= 44.4
3. Fuel costs= $623.33.

Conclusions:
1. Apparently, the reports that the trip ODO MPG is off to the high side are true.
* As noted above, this has been uniformly verified in other Post/Threads.
2. The advertised improved mileage for the Gen III is exaggerated (though 44.4 is still impressive).
* The Test run by the NHTSA is identicle for ALL cars. Their results are their results.
I realize the engine in the Gen III is larger than the Gen II's, so achieving the same mileage with a larger engine is an improvement.
* Very perceptive.
Regarding my driving style: I don't go to extremes to eke out extra miles per tank. I drive the Prius like a car. I live in a hilly region which often requires a lot of time in the red zone.
* Your driving style is probably not as big a contributor to your mileage (or lack thereof) as your driving environment.

You may have relatively short comutes in a hilly region, and those conditions are not condusive to stellar mileages.

Have you made attempts to drive in the Eco area of the HSI?

What Mode are you now driving in: ECO, Normal or PWR? Others have found that changing their current Mode to one of the others will allow them to increase mileage.

I still love the Gen III, but I've shelved my dreams of 50 MPG.

* Realistically, that figure may not be attainable in your particular circumstance.

David (aka Blind Guy)

[tekgirl]

Originally Posted by bps

I'm sorry to hear that. I have 2,850 miles on my Gen III with a 59.2 avg (computer, not actual).

Bryan

I am taking it to the dealer next week and will try to figure out what the issue is. I realize that 42mpg is better than 20, but I was expecting a bit more

[john1701a]

Originally Posted by tekgirl

I am taking it to the dealer next week and will try to figure out what the issue is. I realize that 42mpg is better than 20, but I was expecting a bit more

What kind of checks have you done?

Try this: Verify tires are at an absolute minimum of 33 PSI cold. Get out onto the highway. Set the cruise. Reset a trip meter.

At 60 MPH, you should see dramatically higher MPG average. If so, there's probably nothing wrong and it's just your routine driving causing the lower MPG.
.

[bwilson4web]

Normally we find a Gaussian distribution in any population:

MPG	EPA ZVW30 (47)	PC ZVW30 (121)	07-09 NHW20 (284)
32.5	0%	2%	1%
37.5	2%	0%	6%
42.5	4%	6%	23%
47.5	23%	24%	36%
52.5	38%	40%	26%
57.5	28%	22%	5%
62.5	4%	5%	2%
67.5	0%	1%	1%

.
About a 1/3 achieve 52.5 MPG. About 1/3d are lower and 1/3d are higher. But we've only had the 2010 Prius in our hands for less than a year and the North American ones have yet to go through winter.

It is entirely possible that after a year, the ZVW30 and NHW20 will have similar milage. Winter is the season we'll learn the effectiveness of the exhaust heat recovery system. Wayne has already published some preliminary data and I'm hoping we'll see an update when the ambient temperatures are closer to 32F/0C.

Bob Wilson

[tekgirl]

Originally Posted by john1701a

What kind of checks have you done?

Try this: Verify tires are at an absolute minimum of 33 PSI cold. Get out onto the highway. Set the cruise. Reset a trip meter.

At 60 MPH, you should see dramatically higher MPG average. If so, there's probably nothing wrong and it's just your routine driving causing the lower MPG.
.

Thanks - I'll give it a try...when I first started driving the car, I was getting over 51 mpg and my driving/route has not changed. haven't really done any "checks" per se - I wanted to do some reading here first and see what others are getting as far as mpg.

[bwilson4web]

Hi,

Originally Posted by tekgirl

. . .
I have a Gen V, which is loaded but I was getting better gas mileage when it was new. It now has a little over 3000 miles. Can anyone shed some light on this?

Studies with the NHW11 and NHW20 have revealed:

• battery efficiency - is at a peak for the first 3-4 months and then reaches a plateau for the life of the car. We've seen a short term improvement, 3-4 months, in mileage after traction battery replacement.
• transaxle oil - although still under study, it looks like an early replacement returns transaxle rolling drag to like new status. We just don't know how long this effect lasts, which is why it is still under study.
• bumper air inlet blocking - improves warm-up in the earlier cars and reduces cooling drag at lower temperatures.

The car is so efficient that most user modifications and maintenance are in the 1-5% range ... well within the MPG noise. It takes careful attention to detail to quantify these effects.

Bob Wilson

[globalcivilian]

Originally Posted by tekgirl

I am only averaging 42 mpg and am wondering if something is wrong. My driving is a mix of highway/local and a friend who travels the same route is getting over 50 with her Gen 2.

I have a Gen V, which is loaded but I was getting better gas mileage when it was new. It now has a little over 3000 miles. Can anyone shed some light on this?

Thanks

I've only had mine about 2 weeks, but find I'm getting 2 mpgs more this week than last. I think it's because I've discovered how to drive it more to still in the Hybrid Eco area.

How long have you been driving yours? Are you keeping it in the Eco and then releasing the pedal to get it into the Hybrid Eco Area once you achieve the speed that you want? Have you checked your tire pressure to make sure it has not dropped significantly? I have mine at 35 front and 33 rear. I think the model's V have a different recommended psi though..

[mgb4tim]

Originally Posted by Paradox

We have Prius v's as well, so the 17" rims and their tires are hurting us as well. If you had a Prius II-IV you would see an improvement over the GenII.

How are 17" rims hurting if the tire diameter is the same?

[Paradox]

Originally Posted by mgb4tim

How are 17" rims hurting if the tire diameter is the same?

The 17" rims are heavier and the tires that go on also hurt fuel mileage over the 15"s...

[wvgasguy]

Originally Posted by Coastie

Passed the 10k point a few days ago. So far, the MPG is essentially the same as what my Gen II Prius gets (2004 with 103k miles).
Here's the data:
1. The trip ODO average MPG for the 10,000 miles= 46.4
2. Actual computation of MPG for the 10,000 miles= 44.4
3. Fuel costs= $623.33.

Conclusions:
1. Apparently, the reports that the trip ODO MPG is off to the high side are true.
2. The advertised improved mileage for the Gen III is exaggerated (though 44.4 is still impressive).

I realize the engine in the Gen III is larger than the Gen II's, so achieving the same mileage with a larger engine is an improvement.
Regarding my driving style: I don't go to extremes to eke out extra miles per tank. I drive the Prius like a car. I live in a hilly region which often requires a lot of time in the red zone.

I still love the Gen III, but I've shelved my dreams of 50 MPG.

I live in WV (hills) and am getting just barely a little better than you. However even at 45 mpg, I "am" impressed It's not what I had hoped for but with the low profile wide tires and a lot of highway driving making up most of our miles I'm satisfied. Had we not gotten the "V" we both may have a little better results. I do find that driving the back roads at 50 mph I can indeed get 55mpg. I just don't have the time to do that most of the time.