POLL - Actual Computed Mileage

[treeofliberty]

I maded my first "real" fillup this afternoon after a controlled experiment that involved 4 roundtrips to/from work. The route is about 70% highway, and has very much elevation change (through Phoenix) and is 38.5 miles one way. The weather has been relatively cool in the mornings and topping out around 109 for the trip home. The car stated 43.6mpg for this period, but the actual computed miles from the fillup is 41.25.

 

I don't buy all the crap in the manual about why the two might differ (you filled up on a hill, blah blah blah). I'll be curious to see if this starts to track more accurate over time. Either way, I'm very happy with the results thus far, utilizing moderate "hypermiling" techniques.

 

Hey wstcoaster07, we're of a similar mold. My lifted Wrangler also gets 15.3mpg. What a great change of commuter vehicles.

[wstcoaster07]

Hey wstcoaster07, we're of a similar mold. My lifted Wrangler also gets 15.3mpg. What a great change of commuter vehicles.

 

Awesome. Do you miss the pickup/power from the jeep a LOT or does it not bother you that much? I don't floor the jeep but you can still just feel the v8 every time you push the gas and didnt realize how good that felt until I test drove the FFH and didn't have that.

 

Either way, I am keeping my Cherokee simply because I would most likely only get 4-5k for the trade and it runs fine. Plus, I will use it for when going to the Mtns and taking the dog to the beach and stuff.

[treeofliberty]

Either way, I am keeping my Cherokee simply because I would most likely only get 4-5k for the trade and it runs fine. Plus, I will use it for when going to the Mtns and taking the dog to the beach and stuff.

 

Actually, my Jeep is a 2004 Wrangler Unlimited:

 

 

So, while the 4.0 is pretty peppy, it was nothing like your Grand. As far as acceleration goes, the comparison between the Wrangler and the Fusion is about even, with a slight edge to the Ford. You may find that the "game" of hypermiling gives a different set of gradification, especially with all the cool graphics.

[treeofliberty]

The car stated 43.6mpg for this period, but the actual computed miles from the fillup is 41.25.

 

It is surely a sign of self-absorption when you quote yourself...

 

I forgot to mention one detail that may explain some of the difference. At the beginning of this period, I filled up in the morning (about 77 degrees) and at the end I filled up in the afternoon, at (about 102 degrees).

[WPWoodJr]

I maded my first "real" fillup this afternoon after a controlled experiment that involved 4 roundtrips to/from work. The route is about 70% highway, and has very much elevation change (through Phoenix) and is 38.5 miles one way. The weather has been relatively cool in the mornings and topping out around 109 for the trip home. The car stated 43.6mpg for this period, but the actual computed miles from the fillup is 41.25.

 

I don't buy all the crap in the manual about why the two might differ (you filled up on a hill, blah blah blah). I'll be curious to see if this starts to track more accurate over time. Either way, I'm very happy with the results thus far, utilizing moderate "hypermiling" techniques.

 

Hey wstcoaster07, we're of a similar mold. My lifted Wrangler also gets 15.3mpg. What a great change of commuter vehicles.

So like me you're getting 6% or so less actual mileage than what the computer says. Hopefully it will get more accurate as the car wears in.

 

I'm also coming from a car that gets low mileage - 1998 Audi A6, I could never get more than 16 mpg around where I live doing mostly hilly suburban driving.

[Oman]

The mileage display on the vehicle will never be completely accurate. When you think about what it is doing it is pretty amazing... it is measuring the precise amount of fuel passing through the injector each time the injector fires, and adding that up. It needs to know the exact fuel pressure, temperature, and the exact distance traveled. Even adding 2 pounds of pressure to the tires will cause the calculation to go off (the distance traveled per rotation will change ever so slightly). To that end your own calculation based on gallons added will never be totally accurate either as it also relies on the distance on the odometer which will be off based on tire pressure too.

 

If you check your pressure very consistently, like every morning using your own gauge and being very precise then at least you can keep your measurements consistent.

 

Jon

 

 

So like me you're getting 6% or so less actual mileage than what the computer says. Hopefully it will get more accurate as the car wears in.

 

I'm also coming from a car that gets low mileage - 1998 Audi A6, I could never get more than 16 mpg around where I live doing mostly hilly suburban driving.

[WPWoodJr]

The mileage display on the vehicle will never be completely accurate. When you think about what it is doing it is pretty amazing... it is measuring the precise amount of fuel passing through the injector each time the injector fires, and adding that up. It needs to know the exact fuel pressure, temperature, and the exact distance traveled. Even adding 2 pounds of pressure to the tires will cause the calculation to go off (the distance traveled per rotation will change ever so slightly). To that end your own calculation based on gallons added will never be totally accurate either as it also relies on the distance on the odometer which will be off based on tire pressure too.

 

If you check your pressure very consistently, like every morning using your own gauge and being very precise then at least you can keep your measurements consistent.

 

Jon

Good points, but as for the tire pressure, as long as the tire pressure doesn't keep changing, it should be the same for the manual and automatic fuel efficiency calculations and would not be a factor.

[KarenD]

Not too shabby. What kind of driving (X hwy, X city). Oh, what hwy speeds are you doing?

 

This tank was mostly my commuting, which is around 40 miles each way, about half highway and half surface streets (most with 40 - 45 mph speed limits). On the highway, I usually average 65 to 70 mph (sometimes a little less if I hit the traffic wrong).

 

I filled up last night and got 41.318 mpg on that tank, which included a 6 hour mostly freeway trip at 70 mph with the AC on.

[billwat]

Not too shabby. What kind of driving (X hwy, X city). Oh, what hwy speeds are you doing?

 

I am still waiting on mine to arrive (end of July I think) and curious as to what kind of mileage I will get. Here in south TX hwy speed is 70mph... not awesome for efficiency, not to mention will need some serious A/C for the summer heat

 

 

I've had mine for about a week now. My daily commute is: 3 mi rural road (45 mph), 7.5 mi rural highway (65 mph), 5 mi. interstate highway (70-75 mph) and 1.5 mi city streets (25-40 mph).

 

Without A/C on my commute I've been getting about 40-41 mpg (according to the trip readout). With A/C makes a noticable difference, brings it down to 35-36 mpg.

 

I live in SW Oklahoma, so A/C is pretty much a necessity. I just filled up at 1/4 tank remaining and came out that in the first week of ownership I've averaged about 34.45 mpg.

[WPWoodJr]

I posted this MPG update in my blog:

 

Today I filled up the tank. For consistency I went to the same pump I used last time. The car took 9.826 gallons (with no "top off"); the tank mileage was 434.6 miles, leading to an average of 44.23 mpg.

 

The car's MPG reading, which I had reset before this tank, was 45.2 mpg; it seems to be reading a little high (2% in this case and 6% high last time).

 

Driving conditions were approximately 45% highway (55-65 mph), and 55% suburban, rolling-to-hilly terrain. I generally left A/C off but not always.

 

Not bad for a car whose EPA rating is 41 city / 36 highway! :happy feet:

[wstcoaster07]

highway (55-65 mph)

 

Thanks for the update... Grandma

 

TX hwy posted speed is 70.. I think if I drove 10 under that I would be shot.

[rlawson4]

I just filled up tonight. I went 600.4 miles and filled 15.13 gallons = 39.68. The gauge said I averaged 41.1 However, there is no way to know if I could have forced more gas into the tank. my driving is about 55% highway 45% City. I have made my attempt to drive with mpg in mind. As stated in my other posting, right around 1000 miles, my mileage has increased 2 mpg.

[KarenD]

This morning I put 14.216 gallons in, having gone 596.1 miles since my last fillup, for 41.93 mpg. This tank was my typical half freeway/half city commute. I've got a little more than 4800 total miles on the car, and my dash long term mpg has been showing around 42.2.

[tencargarage]

I have had my FFH for a week and driven about 320 miles. The tank is now half full. The A/C is on all the time. I do no special driving to increase mileage, 65 max MPH, mileage mix hwy, 35 % city 65%.

 

Dash mileage showing 38.2

 

I am pretty happy with that.

[lrymal]

I almost have 1000 miles on my FFH and at about 900 miles, it as if the economy gods woke and decided to get to work. My mileage has been improving consistently during the past 200 miles, and especially the last 80. I am very pleased and am happy to report a high average (consistently duplicated, but not typical) of 44 - 45 mpg, and a very easy to duplicate commute mileage of 42 - 43 mpg. This is about 10 mpg better than what the car had with zero miles. I am about 50 - 50 mix with city and highway with lots of hilly roads.

 

Obviously, my driving habits for hybrid driving have been coming "online" as well during this time.

[jeff_h]

After 20 days, I'm happy with it thus far and it should get better (if you track tank by tank you'll get the true MPG since it compensates for short fills here or there). But don't be surprised if the MPG tanks when the weather gets cold, the winter weather used to knock my Prius MPG down by about 8-10% on average, if this hybrid system is similar I expect a similar cold-weather hit.

 

Date | Miles | ODO | Gal | MPG

7/8/09 | 509 | 517 | 13.80 | 36.90

7/9/09 | 482 | 999 | 12.67 | 38.04

7/13/09 | 367 | 1366 | 10.10 |36.34

7/15/09 | 556 | 1922 | 13.91 | 39.97

7/21/09 | 525 | 2447 | 13.06 | 40.20

[lrymal]

I need to start a journal...

 

Well, I expect the mileage to really drop this winter. I think the manual even states that. Winters here are mild so hopefully I won't be bit as bad as you folks up north. Temperatures in the 30s are about as cold as it gets, with 40s-50s more typical.

[tonifan]

Does anyone know for a fact if the Prius' solar powered roof is for the A/C, or just for keeping the car ventilated when it's parked? Does the A/C run solely (pardon the pun) on solar power? Doesn't seem likely that the solar panels would be used to keep the car's air conditioning running when the car is being driven. Are there any accurate specs on how either the solar panels or the A/C operates in drive vs. parked mode on the Prius?

 

P.S.: While on my daily commute, with A/C set at 69 degrees in my FFH, I still get 42.1 mpg to and from work with a 48-mile total commute. (And that includes all those great San Francisco hills!)

 

P.P.S.: The temperature where I work is usually 18-20 degrees warmer than San Francisco, where I live.

[rfruth]

The Prius solar roof option puts out 50 watts and runs a fan (not the a/c)

 

Prius solar roof

 

said differently I plan to leave the moonroof cracked to allow heat to escape - if promoting the technology is important (which is what the Prius solar roof option is doing) see here

[ralteredstates]

$2000 option for the solar roof!! WOW, for that price I can travel over 30,000 miles in my FFH and have coffee money left over. Not the smartest option. Reminds me of the self park option I didn't go for on my previous car. Waste of $$$.

[cuehara]

40.1 mpg w/90% highway and single occupant (mixed a/c usage) with approx 2000 miles. Drive is mildly hilly.

[KarenD]

My latest tank (at about 6000 miles total) was my best so far: 674 miles and 15.671 gallons for an average of 43.01 mpg. That's mostly all my normal half city/half freeway commute with AC on most of the time (it is summer here still).

[VonoreTn]

We just got our Fusion Hybrid August 20. Only data so far is 526 miles, 12.29 gallons, 42.9 mpg. Impressions: The gas engine comes on when it's gonna come on, I don't seem to have much control of it. A light throttle foot correlates with good mileage, based on resetting the mpg gauge a few times in that 526 miles, despite speed, hills, traffic or other variables that can ruin your mpg on a regular car. When I say despite hills, I mean assuming your whole trip is not up-hill. You can't' fight physics. It has ample power for our purposes, basic transportation.

 

I am surprised at how little I can see of any part of the electric motor under the hood. There are covers on everything, they obviously don't want you messing with this powertrain. Even though I'm a engineer, and installed a supercharger on our Mustang, our second car, I have no plans to tamper with this car, ever.

 

There is like a fan that comes on before the engine comes on, I'm guessing its the AC condenser fan, and it seems to be really loud. I may have to have that looked at.

 

So far we like the car a lot. My Wife is really into trying to get the mileage as high as possible on every trip. Once we get used to this kind of mileage, it will be hard to go back to a 20 mpg vehicle. We have a 2000 mile plus trip coming up in a week, we should have more impressions and data after that.

[Oman]

The electric motors are integrated directly into what kinda looks like the transmission (which it is). For the power output they are actually pretty small. The power controller is also integrated into the main housing with just a service cover to facilitate repairs. If you peek around under the hood you can pretty much see the 4cyl ICE to the center-left and then a shiny cover to the right between the strut brace, the ICE, and the battery. That is the top of the electric power unit. It runs down alongside the ICE. Inside that unit are 4 main parts. There is a planetary gear system with a motor driving the sun gear (MG1), a larger motor (MG2) drives the output shaft after reduction right along with the output of the planetaries. The planetaries are the only thing that could be considered a transmission.

 

If you look around on the 'net you can find some pictures of the Prius drive unit. The FFH has a similar mechanical design but they seemed to have packed it all in better, considering that the FFH delivers more power through both systems yet it isn't much bigger.

 

Jon

 

 

We just got our Fusion Hybrid August 20. Only data so far is 526 miles, 12.29 gallons, 42.9 mpg. Impressions: The gas engine comes on when it's gonna come on, I don't seem to have much control of it. A light throttle foot correlates with good mileage, based on resetting the mpg gauge a few times in that 526 miles, despite speed, hills, traffic or other variables that can ruin your mpg on a regular car. When I say despite hills, I mean assuming your whole trip is not up-hill. You can't' fight physics. It has ample power for our purposes, basic transportation.

 

I am surprised at how little I can see of any part of the electric motor under the hood. There are covers on everything, they obviously don't want you messing with this powertrain. Even though I'm a engineer, and installed a supercharger on our Mustang, our second car, I have no plans to tamper with this car, ever.

 

There is like a fan that comes on before the engine comes on, I'm guessing its the AC condenser fan, and it seems to be really loud. I may have to have that looked at.

 

So far we like the car a lot. My Wife is really into trying to get the mileage as high as possible on every trip. Once we get used to this kind of mileage, it will be hard to go back to a 20 mpg vehicle. We have a 2000 mile plus trip coming up in a week, we should have more impressions and data after that.

[GreenGene]

Ok...now I'm jealous. I just rolled over 1,500 miles on my FFH and am still on my 4th tank. My average so far is 28.5. So I guess I win the award for lowest possible mileage. Now to clarify, it's been 110 - 115 degrees over the last few weeks so the a/c is on full blast 100% of the time. Even though my mpg is lower than everyone's, it is still double my last car so I'm very pleased. I can only assume that when summer ends, my mpg will increase dramatically.