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Old 11-26-2012, 09:04 AM   #26
s1eepR
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You touched on running heater all the time. I noticed...unlike my other cars when the fan is set to zero and the temp is neutral, there's still substantial airflow from the vents. I know some is to be expected but it seemed to be more than other cars I've driven. I'm a cheapster and try to hypermile but how can I be sure it's completely off?
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Old 11-26-2012, 02:45 PM   #27
Counterfit
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If the fan is set to zero, no power is being drawn. The airflow is because of high pressure at the intake, which is at the base of the windshield.
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Old 11-26-2012, 07:07 PM   #28
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Another thing, I thought heat was "free" and the only cost was the fan as compared to the A/C which uses more resources. Correct me?
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Old 11-26-2012, 08:17 PM   #29
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The front defroster positions turn on the A/C compressor, so if you stay out of those, it will only draw power for the fan if you have it on. There may be thermodynamic concerns about removing heat from the system in cold weather, but I'm pretty sure that the engine produces more than enough even below freezing.
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Old 11-26-2012, 09:41 PM   #30
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I'm going to "take one for the team" and try out ethanol free gasoline and see how much difference there is as opposed to the E15 winter blend. I've been tracking my fuel mileage for a little over 20k miles (I drive a lot) and thus far have seen as high as 26 on E10 and as low as 17 all last winter with a dodgy o2 sensor.

It would be my guess that the components of my older (97) car are designed to run on non ethanol gas as it were, and as such my improved power and mpgs will offset the added costs. Seems legit, right?
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Old 11-27-2012, 11:58 PM   #31
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Quote:
Originally Posted by Pickler View Post
i don't think i was clear enough about ethanol. As i said i tried both ethanol free shell vpower and the 10% ethanol containing petro canada 87 octane and i saw no difference in mileage or power. The only difference was the car running slightly lean above 4000rpm with vpower (i think 11:1 vs 10.8:1 at 6000rpm). Also i have been running 10% ethanol 87 octane gas in summer time with no issues, scoring 33mpg highway and 24mpg city consistently. Now my problem is the winter gas, it just seems to evaporate in there. about 18mpg city and 26 highway. it seems i'm right, according to petro canada's website:

http://www.petro-canada.ca/en/wholesalefuel/318.aspx
Ummmmm.....yes, it evaporates more easily, but (this is a biggie....) you have a "sealed fuel system" because of emissions. Or, at least you SHOULD have a sealed system. If you had leaks (at least, leaks big enough to "see" a drop overnight) you would also get a CEL for "evap controls".

PS, yes, my 1998 2.5 NA see's a mileage drop every year when winter gas arrives.
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Old 11-28-2012, 04:33 PM   #32
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my second tank of gas since i made this thread came out to 19mpg today. this included total avoidance of idling, more coasting and driving without brakes. lowest so far in my mileage log:
http://www.fuelly.com/driver/pickler/impreza

i don't know if it's the evaporation or what not but it just sucks. my impreza is getting the lowest MPG of all my cars and this includes a 4000lbs, 2.3T RDX.

question when your coasting below 45mph and drop in neutral does your rpms climb to ~1200rpm?

Last edited by Pickler; 11-28-2012 at 04:55 PM.
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Old 11-29-2012, 03:07 PM   #33
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J-hop,
I live in Edmonton where it has almost every year since I have been driving, 1971, hit -40degrees F/C, as they are equal at that temperature, for more than a few days. Anyone that complains about a loss of fuel mileage that is not in the -15 to -20 degrees F has absolutely nothing to complain about in my opinion. Also we have it pretty good compared to the folks living in North of us as they typically see much lower temperatures for a longer period of time.

Regards,

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Old 11-29-2012, 03:10 PM   #34
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Decided to fill with Ethanol free yesterday. $4.499 per gallon; 28% more than E10 premium costs. By that math, I need to be averaging around 28mpgs on ethanol free for it to be a wash in cost. I do notice my car runs better and doesn't stumble when it's cold; in and of itself may be worth the added costs.
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Old 11-29-2012, 09:34 PM   #35
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Quote:
Originally Posted by cal_look_zero View Post
Decided to fill with Ethanol free yesterday. $4.499 per gallon; 28% more than E10 premium costs. By that math, I need to be averaging around 28mpgs on ethanol free for it to be a wash in cost. I do notice my car runs better and doesn't stumble when it's cold; in and of itself may be worth the added costs.
According to the US Department of Energy, E10 will hurt your fuel economy 3-4% compared to gasoline.

http://www.fueleconomy.gov/feg/ethanol.shtml

If you want to see how to gauge ethanol pricing correctly, take a look at Brazil.

http://en.wikipedia.org/wiki/Flexibl...cles_in_Brazil
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Old 11-30-2012, 07:43 AM   #36
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just filled up yesterday, and got 17 mpg, average temp here last week -20c ~ -15c (~zero f) coming from someone who consistently averaged 33+ all summer

https://www.fuelly.com/driver/eduva1/impreza

WINTER GAS SUCKS!
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Old 11-30-2012, 08:41 PM   #37
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Quote:
Originally Posted by Duvanator View Post
just filled up yesterday, and got 17 mpg, average temp here last week -20c ~ -15c (~zero f) coming from someone who consistently averaged 33+ all summer

https://www.fuelly.com/driver/eduva1/impreza

WINTER GAS SUCKS!
NO
Just winter sucks ie: cold
Your loss of mileage is due to cold start up! Motors must run rich for the start up and there goes your mileage. If you have an air ratio gauge (wide or narrow band) it will show you how long it is rich.
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Old 12-02-2012, 04:55 PM   #38
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According to the US Department of Energy, E10 will hurt your fuel economy 3-4% compared to gasoline.

http://www.fueleconomy.gov/feg/ethanol.shtml

If you want to see how to gauge ethanol pricing correctly, take a look at Brazil.

http://en.wikipedia.org/wiki/Flexibl...cles_in_Brazil

ALWAYS try to run ethanol free gasoline. No cars come factory with the ability to properly run ethanol blended fuel with the exception of flex fuel vehicles.

Ethanol contains oxygen in the molecular make up so even though it has a higher octane rating you can't truly benefit from it because your O2 sensor reads a lean condition (due to the added oxygen present in the ethanol)and your ecu tries to compensate by richening the mixture to the correct afr. As a result you get worse fuel economy(compounded by the lower energy content)
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Old 12-02-2012, 05:16 PM   #39
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Originally Posted by J-hop View Post

ALWAYS try to run ethanol free gasoline. No cars come factory with the ability to properly run ethanol blended fuel with the exception of flex fuel vehicles.
Pretty sure every single gas station I've ever been to (atleast in PA) has 10% ethanol in all their gas.

Pump: "contains up to 10% ethanol"

Last edited by ManualOverAuto; 12-02-2012 at 05:25 PM.
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Old 12-02-2012, 05:36 PM   #40
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Yea it is probably pretty hard to find regular and mid grade in the non ethanol blended variety in the US. But you may still be able to get premium in a non ethanol blend if your car requires premium which probably doesn't apply to most in the NA forum.

I don't quite understand the US regulation but where I live gas stations are required to sell x% of their total volume as ethanol. Luckily this means reg and mid are often the ones blended but at most places the premium is not.
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Old 12-02-2012, 05:45 PM   #41
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I am not trying to argue that ethanol is better, I am simply saying that spending any time worrying about the ethanol content in E10 is a waste of time.

E10 is not harmful:
All auto manufacturers approve the use of E10 in their vehicles. This means that the vehicles are designed to handle this level of ethanol. If they were not able to survive these conditions, you would see a huge trend in engine failures due to ethanol in the winter weather states. Even if you were to believe that some manufacturers have issues with E10, Subaru makes it's bread and butter in the winter climates (where E10 is more prevalent). Their reliability and longevity record is testament to the fact that E10 is not causing critical failures in Subarus.

Cost of E10:

400 miles / 25 mpg * $4 per gal. = $64 in gas
400 miles / 24 mpg * $4 per gal. = $66.67 in E10. ($2.67 per tank difference)

If I were to drive 4000 miles in the winter, the difference in cost would be $26.70 for the whole winter between E10 and pure gas.

To look at it another way, at $4 per gallon, E10 costs you roughly $0.16 per gallon.
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Old 12-02-2012, 05:47 PM   #42
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Originally Posted by J-hop View Post
I don't quite understand the US regulation but where I live gas stations are required to sell x% of their total volume as ethanol. Luckily this means reg and mid are often the ones blended but at most places the premium is not.
The large corn farming community and their lobbyists might have something to do with that . There was a push a few years ago to raise E10 to E15.
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Old 12-03-2012, 11:06 PM   #43
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my afr shows 13.8-14.4 cold start i will film a cold start tomo with my iphone and well see. the car has been off for 4 days in freezing temps. but tomo is supposed to get mild @40'f.
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Old 12-04-2012, 11:00 PM   #44
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Originally Posted by Charlie-III

Ummmmm.....yes, it evaporates more easily, but (this is a biggie....) you have a "sealed fuel system" because of emissions. Or, at least you SHOULD have a sealed system. If you had leaks (at least, leaks big enough to "see" a drop overnight) you would also get a CEL for "evap controls".

PS, yes, my 1998 2.5 NA see's a mileage drop every year when winter gas arrives.
most car built before 2000 dont have evap monitors so a cel will not turn on if he has a leak i should know im a emissions tech
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Old 12-05-2012, 10:24 PM   #45
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last night we had a cold snap (25'f) and so this morning when i started the car the AFR was stuck at 14.6 and not moving until car went into closed loop (i tried applying throttle, changing gears but it wouldn't change). strangely enough day before that with 48'f temps when i started the car AFR showed 12.7-13 for a bit then went to low 14s. im thinking something is wrong with my O2 sensor or perhaps it doesnt report AFR until its warm. If so when it's cold and O2 is not reporting AFR to ecu, and it is in open loop for a while, then it is probably pumping much more fuel than it expects (running very rich). tonight gonna be 10 degrees so ill keep my eye on afr again. my current average trip mileage is 20 MPG.

Last edited by Pickler; 12-05-2012 at 10:33 PM.
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Old 12-05-2012, 11:07 PM   #46
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25*F?! Man I wish we had those temps. In AK we're at -15*F and 20mph winds.
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Old 12-05-2012, 11:09 PM   #47
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25°F is not a cold snap.
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Old 12-06-2012, 04:27 PM   #48
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lol maybe im getting my Fahrenheit wrong, it was -10'c. it was 12'c the day before so it was a big drop in temp. and yes i expect no more than -15f in alaska lol. i'm driving up to churchil during the holidays with my impreza (followed by my friend with his toyota hilux). i have gotten the tire chains, extra battery and my fluids straight. i'm expecting -50'c windchill which i think is -60'f ?? and perhaps 10MPG with the rate my impreza is going with temp drops.

Last edited by Pickler; 12-06-2012 at 04:33 PM.
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Old 12-06-2012, 04:28 PM   #49
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That's 14°F, which is almost a cold snap.
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Old 12-06-2012, 07:51 PM   #50
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I just have the urge to note, that we just had a "cold snap". The low all week is going to be below, 50 degrees F.

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