Welcome to the North American Subaru Impreza Owners Club Thursday March 28, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Subaru Models > Impreza Forum

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 07-11-2012, 09:25 AM   #1451
auskip07
Scooby Specialist
 
Member#: 315643
Join Date: Apr 2012
Chapter/Region: South East
Location: Atlanta Ga
Default

Quote:
Originally Posted by Haunty View Post
I noticed the first half of the bars go slower, the last half of the bars drop quickly. My last car was like that too.
Every car i have owned seem to do that also. from my 88 chevy blazer to 2012 subaru.
* Registered users of the site do not see these ads.
auskip07 is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 07-11-2012, 10:25 AM   #1452
SleepNMnky
Scooby Specialist
 
Member#: 302491
Join Date: Nov 2011
Chapter/Region: Tri-State
Location: Buffalo, NY
Vehicle:
2012 Impreza 2.0i Pr
Dark Grey Metallic CVT

Default

This link goes into it a little saying that the fuel gauges are notoriously inaccurate. I've always noticed the same trend, more miles out of the first half of the tank than the second. According to this it's just the way the gauge reads it. Also, even with the low fuel light on & after I've hit the one bar left & continue to drive past that for say another 20 miles, the tank is certainly not near Empty. When I fill up I get 12.5 gallons at most in that tank so actually at 30mpg there's still be at least another 45 miles I could get out of the tank. So that low fuel light must be calibrated for when there is still 1.5-2 gallons left in the tank. I don't make a habit out of running it to E but that one bar left & low fuel light I'd say gives you at least another 50 miles.
http://auto.howstuffworks.com/fuel-gauge.htm/printable
SleepNMnky is offline   Reply With Quote
Old 07-11-2012, 10:32 AM   #1453
Ladeef
Scooby Newbie
 
Member#: 318753
Join Date: May 2012
Chapter/Region: South East
Vehicle:
2012 Impreza
Dark Grey

Default

Quote:
Originally Posted by SleepNMnky View Post
This link goes into it a little saying that the fuel gauges are notoriously inaccurate. I've always noticed the same trend, more miles out of the first half of the tank than the second. According to this it's just the way the gauge reads it. Also, even with the low fuel light on & after I've hit the one bar left & continue to drive past that for say another 20 miles, the tank is certainly not near Empty. When I fill up I get 12.5 gallons at most in that tank so actually at 30mpg there's still be at least another 45 miles I could get out of the tank. So that low fuel light must be calibrated for when there is still 1.5-2 gallons left in the tank. I don't make a habit out of running it to E but that one bar left & low fuel light I'd say gives you at least another 50 miles.
http://auto.howstuffworks.com/fuel-gauge.htm/printable
Owners manual states reserve fuel is about 2.5 gallons, once the light comes on.
Ladeef is offline   Reply With Quote
Old 07-11-2012, 10:57 AM   #1454
ocellaris
Scooby Specialist
 
Member#: 302559
Join Date: Nov 2011
Default

Fuel tanks always read E before they are actually empty because the fuel also acts as coolant for the fuel pump. Running out of gas sucks, but then running out of gas and then having to buy another fuel pump sucks even worse than that. Often when people run out of gas, then get more gas into the car, it will not start. Fuel pumps are not cheap.

Also when you really run out of gas, the fuel filter can pickup stuff it would not normally pickup and cause a problem in the fuel filter.

Cars are not like lawnmowers. Running out of gas is really bad for the fuel system.
ocellaris is offline   Reply With Quote
Old 07-11-2012, 11:26 AM   #1455
sgoldste01
Scooby Specialist
 
Member#: 322264
Join Date: Jun 2012
Chapter/Region: Tri-State
Location: Webster, NY
Vehicle:
2012 Impreza Sp 5sp
Obs Blk Prl/Drk Gray Mtl

Default

Which is why I start looking for a gas station at around 300 miles since my last fill up, regardless of how many segments are showing on the gas gauge.
sgoldste01 is offline   Reply With Quote
Old 07-11-2012, 11:41 AM   #1456
kevinsUBARU
Scooby Specialist
 
Member#: 2263
Join Date: Sep 2000
Chapter/Region: Tri-State
Location: Hudson Valley
Vehicle:
2014 Sportwagen TDI

Default

In my experience the gauge will run out and with the light on, it's something like 40 miles left on the display. When I reach 400 miles past my last fill, I look for a station.
kevinsUBARU is offline   Reply With Quote
Old 07-11-2012, 11:46 AM   #1457
Impreza1228
Scooby Newbie
 
Member#: 325234
Join Date: Jul 2012
Location: NC
Vehicle:
2012 Impreza Pre CVT

Default

I try to never let less than 4 bars appear before I fill up. The reasoning is to prevent pickup of any contaminates they may be in tank.
Impreza1228 is offline   Reply With Quote
Old 07-11-2012, 12:50 PM   #1458
Haunty
Scooby Newbie
 
Member#: 319378
Join Date: May 2012
Chapter/Region: MWSOC
Location: West Central MN
Vehicle:
2012 2.0i Sport Ltd.
Satin White Pearl

Default

I had my fuel pump replaced on my last car, it cost over $700 installed, but it was over 100k miles.
Haunty is offline   Reply With Quote
Old 07-11-2012, 01:02 PM   #1459
Impreza1228
Scooby Newbie
 
Member#: 325234
Join Date: Jul 2012
Location: NC
Vehicle:
2012 Impreza Pre CVT

Default

Quote:
Originally Posted by Haunty View Post
I had my fuel pump replaced on my last car, it cost over $700 installed, but it was over 100k miles.

Did you run nearly dry or allow some fuel to remain in tank during this 100K?
Impreza1228 is offline   Reply With Quote
Old 07-11-2012, 01:42 PM   #1460
Haunty
Scooby Newbie
 
Member#: 319378
Join Date: May 2012
Chapter/Region: MWSOC
Location: West Central MN
Vehicle:
2012 2.0i Sport Ltd.
Satin White Pearl

Default

Quote:
Originally Posted by Impreza1228 View Post
Did you run nearly dry or allow some fuel to remain in tank during this 100K?
90% of the time I filled it at about 1/4 tank left.
Haunty is offline   Reply With Quote
Old 07-11-2012, 05:03 PM   #1461
ZionZR2
Scooby Newbie
 
Member#: 319990
Join Date: May 2012
Chapter/Region: TXIC
Location: Austin, TX
Vehicle:
2012 Imp Prm 5D CVT
Dark Grey Metallic

Default

The last 3 tank fills all at the same station and same pump at said station, i can add 2.7 gallons after the pump 1st clicks off. I will usually go 100 miles before the first bar turns off. Then Depending on the drive type Which for me is either Normal city or Extreme city. I can get between 10-20 miles per bar through the rest of the tank.
ZionZR2 is offline   Reply With Quote
Old 07-11-2012, 06:40 PM   #1462
stien
Scooby Newbie
 
Member#: 315086
Join Date: Mar 2012
Chapter/Region: NESIC
Vehicle:
2012 Impreza Premium
5MT 5 Door AWP Just Black

Default

I've been getting 39mpg mixed reliably by not stepping on it too much (manual hatch, '12, premium pkg with no racks). Love this car. I've even been able to get 46 by really, really grannying it.
stien is offline   Reply With Quote
Old 07-11-2012, 08:31 PM   #1463
subiTWO
Scooby Newbie
 
Member#: 273054
Join Date: Feb 2011
Vehicle:
2012 Impreza CVT HB

Default

Quote:
Originally Posted by Impreza1228 View Post
I try to never let less than 4 bars appear before I fill up. The reasoning is to prevent pickup of any contaminates they may be in tank.
The pickup does not float on top of the gasoline. It's at the bottom of the tank.
subiTWO is offline   Reply With Quote
Old 07-11-2012, 08:33 PM   #1464
subiTWO
Scooby Newbie
 
Member#: 273054
Join Date: Feb 2011
Vehicle:
2012 Impreza CVT HB

Default

My first and last bar are very close to 1.5 gallons, while the others are close to 1 gallon. That assumes that my mpg was about the same from the full tank to the empty tank. Since an empty tank is much lighter, that may not be strictly true, though.
subiTWO is offline   Reply With Quote
Old 07-12-2012, 08:43 AM   #1465
Impreza1228
Scooby Newbie
 
Member#: 325234
Join Date: Jul 2012
Location: NC
Vehicle:
2012 Impreza Pre CVT

Default

Quote:
Originally Posted by subiTWO View Post
The pickup does not float on top of the gasoline. It's at the bottom of the tank.
What are you saying the fuel pump inlet is at the very bottom of tank and it does not matter?

Therefore running it to reserve is acceptable?

I find that hard to believe, I think that you should not run any car until is at such small level common sense will tell you if anything is at bottom of tank it will be pickup-ed by fuel pump.

We must use common sense logic regardless of where the pickup is located.
Impreza1228 is offline   Reply With Quote
Old 07-12-2012, 10:15 AM   #1466
Haunty
Scooby Newbie
 
Member#: 319378
Join Date: May 2012
Chapter/Region: MWSOC
Location: West Central MN
Vehicle:
2012 2.0i Sport Ltd.
Satin White Pearl

Default

There can't be that much sediment in the fuel. I mean it's probably filtered at the refinery, it's filtered at the gas station, and again in your car.
Haunty is offline   Reply With Quote
Old 07-12-2012, 11:20 AM   #1467
tomwi53092
Scooby Newbie
 
Member#: 316315
Join Date: Apr 2012
Chapter/Region: MWSOC
Location: Mequon, WI
Vehicle:
2012 Imp HB/Prem/CVT
DCP

Default

Quote:
Originally Posted by Impreza1228 View Post
What are you saying the fuel pump inlet is at the very bottom of tank and it does not matter?

Therefore running it to reserve is acceptable?

I find that hard to believe, I think that you should not run any car until is at such small level common sense will tell you if anything is at bottom of tank it will be pickup-ed by fuel pump.

We must use common sense logic regardless of where the pickup is located.
My question to you is: how do you think the car can draw down the tank dry, or nearly dry, without feeding from the bottom? It can't.

The fuel pump is siphoning from the bottom of the tank, or near the bottom all the time, regardless of the amount of fuel in the tank. Keeping extra fuel in the tank above where it is siphoned off is not protecting anything. It is not preventing any sediment in the tank from being siphoned out. That's OK - the fuel filter will catch any sediment or particles in the tank - that's why it's there.

You're not harming your engine if you run it with a half-gallon of gas in the tank. The only thing that might happen then is if you make a hard turn, the inertia might make the gas move to the side of the tank away from the gas inlet, and the car might sputter momentarily. (Or more correctly, the car will move while the gas will try to stay in place, causing the gas to be at the side of the tank and away from the fuel inlet).

Last edited by tomwi53092; 07-12-2012 at 11:38 AM.
tomwi53092 is offline   Reply With Quote
Old 07-12-2012, 11:56 AM   #1468
sgoldste01
Scooby Specialist
 
Member#: 322264
Join Date: Jun 2012
Chapter/Region: Tri-State
Location: Webster, NY
Vehicle:
2012 Impreza Sp 5sp
Obs Blk Prl/Drk Gray Mtl

Default

How are the fuel pumps in our Imprezas lubricated? I know that in VW TDIs (and other brands too), the diesel fuel provides the lubrication for the fuel pump. But diesel fuel has more lubricating properties (lubricity) than gas, which is why putting gas in a diesel car is so catastrophic. The fuel pump gets destroyed very quickly.

So in a gas car, how is the fuel pump lubricated?
sgoldste01 is offline   Reply With Quote
Old 07-12-2012, 01:40 PM   #1469
ST Eye
Scooby Specialist
 
Member#: 73068
Join Date: Oct 2004
Location: MD
Vehicle:
2008 STI Boost Wagon
2014 Honda Accord Hybrid

Default

Quote:
Originally Posted by tomwi53092 View Post
My question to you is: how do you think the car can draw down the tank dry, or nearly dry, without feeding from the bottom? It can't.

The fuel pump is siphoning from the bottom of the tank, or near the bottom all the time, regardless of the amount of fuel in the tank. Keeping extra fuel in the tank above where it is siphoned off is not protecting anything. It is not preventing any sediment in the tank from being siphoned out. That's OK - the fuel filter will catch any sediment or particles in the tank - that's why it's there.

You're not harming your engine if you run it with a half-gallon of gas in the tank. The only thing that might happen then is if you make a hard turn, the inertia might make the gas move to the side of the tank away from the gas inlet, and the car might sputter momentarily. (Or more correctly, the car will move while the gas will try to stay in place, causing the gas to be at the side of the tank and away from the fuel inlet).
Not likely to get cavitation with the gas in the tank. I have been autocrossing for years with a minimal amount of gas in the tank taking turns harder than you would on the street. I never had an issue. I did however with power steering fluid.
ST Eye is offline   Reply With Quote
Old 07-12-2012, 04:11 PM   #1470
saabarupp
Scooby Specialist
 
Member#: 189032
Join Date: Sep 2008
Chapter/Region: MAIC
Location: Pittsburgh
Vehicle:
2015 STI CWP
'12 Impreza Sport Ltd DGM

Default

The fuel tanks are likely baffled like the oil pans are.
saabarupp is offline   Reply With Quote
Old 07-12-2012, 04:59 PM   #1471
BretAZ
Scooby Newbie
 
Member#: 320866
Join Date: May 2012
Default

Quote:
Originally Posted by saabarupp View Post
The fuel tanks are likely baffled like the oil pans are.
yup....
BretAZ is offline   Reply With Quote
Old 07-12-2012, 05:40 PM   #1472
ZionZR2
Scooby Newbie
 
Member#: 319990
Join Date: May 2012
Chapter/Region: TXIC
Location: Austin, TX
Vehicle:
2012 Imp Prm 5D CVT
Dark Grey Metallic

Default

Best tank so far filled today 14.202 gallons added 393.0 miles driven. (The Low Fuel light was NOT on yet and still showed 2 Bars remained on gauge.)

Calculated 27.7 mpg (Best after 6 fills)
Dash 29.7 mpg avg
A deviation of 2 mpg or 7.2% over
Dash 31 mph avg

E-10( <-- ) 87 Octane Exxon.
I had mixed city driving this tank. instead of mostly extreme city like I usually do. I do Not consider anything within city limits to be highway driving. (even if the road I am on is called a highway)

ZionZR2 is offline   Reply With Quote
Old 07-12-2012, 06:39 PM   #1473
nubsub
Scooby Specialist
 
Member#: 313575
Join Date: Mar 2012
Location: SF Bay Area, CA
Vehicle:
2012 Impreza 2.0i HB

Default

Quote:
Originally Posted by ZionZR2 View Post
Best tank so far filled today 14.202 gallons added 393.0 miles driven. (The Low Fuel light was NOT on yet and still showed 2 Bars remained on gauge.)

Calculated 27.7 mpg (Best after 6 fills)
Dash 29.7 mpg avg
A deviation of 2 mpg or 7.2% over
Dash 31 mph avg

E-10( <-- ) 87 Octane Exxon.
I had mixed city driving this tank. instead of mostly extreme city like I usually do. I do Not consider anything within city limits to be highway driving. (even if the road I am on is called a highway)

whoa! 2 bars remaining and you filled in over 14 gallons. do you do a big top off after the first click?
nubsub is offline   Reply With Quote
Old 07-12-2012, 06:48 PM   #1474
Zeeper
Scooby Specialist
 
Member#: 299286
Join Date: Oct 2011
Chapter/Region: NESIC
Location: Upstate NY
Vehicle:
2017 Legacy Limited
White

Default

Quote:
Originally Posted by nubsub

whoa! 2 bars remaining and you filled in over 14 gallons. do you do a big top off after the first click?
Topping off is dumb and in some vehicles can damage vapor recovery (aka emissions) equipment.

I don't think (actually I am pretty positive, but too lazy to search the owners manual to correct a practice that I don't do) Subaru or any other manufacturer recommends it.

If you are driving in remote areas without gas stations maybe, but for your typical commute it is dumb, just like wanting to force the car into 1st gear above 20mph is dumb.

I'm always left scratching my head and wondering how so many dumb practices are being talked up on this forum. But it's your car, do what you think is excellent.
Zeeper is offline   Reply With Quote
Old 07-12-2012, 07:15 PM   #1475
SleepNMnky
Scooby Specialist
 
Member#: 302491
Join Date: Nov 2011
Chapter/Region: Tri-State
Location: Buffalo, NY
Vehicle:
2012 Impreza 2.0i Pr
Dark Grey Metallic CVT

Default

Quote:
Originally Posted by Zeeper
I'm always left scratching my head and wondering how so many dumb practices are being talked up on this forum. But it's your car, do what you think is excellent.
Nubsub wasn't saying he/she did, just asking how someone could fill to 14.2 gallons. I'm always left scratching my head and wondering how so many people feel the need to call people dumb and school all of us on what they assume us little people don't already know.
SleepNMnky is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
New Impreza owner, low mpg? stuffedcabbage Newbies & FAQs 36 08-28-2017 07:10 AM
2012 Impreza Reviewed - Whytecliff to Seymour brendan_mac Vancouver Impreza Club Forum -- VIC 16 12-23-2011 01:12 PM
NJ Impreza owners - sighting Dan G General Forum Archive 76 10-06-2000 12:24 AM
Md or Va Impreza owners - I have an Impreza related question. Snoopy General Forum Archive 1 06-05-2000 08:08 AM

All times are GMT -4. The time now is 11:32 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.