Ask the Car People.SM


Subaru Legacy/Outback: MPG-Real World Numbers

130 messages,  Last post on May 04, 2012 at 4:49 PM

You are in the Subaru Legacy & Outback Forum.

What is this discussion about? Subaru Outback, Fuel Efficiency (MPG), Sedan, Wagon

Messages Page 12 of 14

#109 of 130 Re: Mileage [lgandad] '97 Outback [kidali] by xwesx

Apr 11, 2011 (9:37 pm)

Replying to: kidali (Apr 11, 2011 7:36 pm)
If the PCV valve is old, that's an easy and cheap replacement. The part might cost $5 and the time perhaps as many minutes. It is absolutely the easiest DIY maintenance one can perform.
 
Another possibility is that the oxygen sensors are giving poor feedback so the car is not trimming the fuel/air ratio as efficiently. I noticed my fuel economy taper off somewhat once I was north of 150,000 miles on my '96 Outback. It used to give me between 22 and 28 mpg (or better!) except during periods of extreme cold (< -25F). In its later life (I had it to 220,000 miles, and it still ran great), the low dropped to about 17 with the tops at about 25. During periods of extreme cold, it would drop as low as 13-14 mpg. I wish I could say I replaced the oxygen sensors and it made a marked improvement, but I planned to replace them in spring of 2007... yet fate had other plans.

#110 of 130 Re: Mileage [lgandad] '97 Outback [kidali] [xwesx] by pilot1226

May 25, 2011 (9:01 am)

Replying to: xwesx (Apr 11, 2011 9:37 pm)
I've had the new `11 Outback 2.5i CVT for a month now, here are my numbers:
 
Highway is about 36 MPG 55 MPH Cruise Control according to the dash computer. (To clarify, this is what's displayed after getting fuel and pulling right back out onto the highway. It actually goes higher - above 40 MPG - but because I typically only drive on a stretch of 5 miles of highway to/from work, it starts to go down when I idle at a light pretty rapidly)
 
Combined over the last 1k miles in the last month between about a 50/50 split of highway & city driving shows me between 26 and 28 MPG, depending on traffic. Not bad at all. Better than my 4AT 09 Legacy 2.5i.
 
I use Trip A for my current tank of gas, and Trip B for the time since last maintenance.
 
I was a big proponent of diesel-based Subarus coming over here and probably would have been one of the first to get them, since the MPG is significantly higher. We'll see what time brings.

#111 of 130 Re: Mileage [lgandad] '97 Outback [kidali] [xwesx] [pilot1226] by ateixeira

May 25, 2011 (9:02 am)

Replying to: pilot1226 (May 25, 2011 9:01 am)
That's very good given the size and accounting for it being AWD. I bet you beat or match a tiny Suzuki SX4.

#112 of 130 Re: Mileage [lgandad] '97 Outback [kidali] [xwesx] by kidali

May 25, 2011 (10:52 am)

Replying to: xwesx (Apr 11, 2011 9:37 pm)
Thanks, xwesx
 
I'll see if I can do the PCV valve myself, and ask my mechanic if he has a test for the O2 sensors before determining if they are the issue.

#113 of 130 Re: Mileage [lgandad] '97 Outback [kidali] [xwesx] [pilot1226] [ateixeira] by pilot1226

May 26, 2011 (8:32 am)

Replying to: ateixeira (May 25, 2011 9:02 am)
Well, I read somewhere that 55 MPH is usually close to the optimal MPG. Every 5 MPH over 55 MPH you travel I think you lose 10% fuel economy. Something along those lines, I think it was on some US Government website. Maybe Department of Transportation / Highway Safety.
 
Anyway, again, the 36 MPG is skewed because it doesn't take into account idling and things like that. For example, the day after when I turned the car on, I gave it about a minute to idle before I put it in gear, and the MPG decreased to around 32MPG. Granted, this also increases once I get the car back out onto highway.
 
I'll have to pen-and-paper some MPG next time I fill it up, since I use the same gas station on my way home from work and we'll see if it corraborates what my trip meter says.
 
Who needs a hybrid, just use your damn cruise control and try driving close to the speed limit!

#114 of 130 Re: Mileage [lgandad] '97 Outback [kidali] [xwesx] [pilot1226] [ateixeira] [pilot1226] by robr2

May 26, 2011 (9:08 am)

Replying to: pilot1226 (May 26, 2011 8:32 am)
Who needs a hybrid, just use your damn cruise control and try driving close to the speed limit!
 
On the highway yes. But in daily city driving, I'd take a hybrid any day. That's where they shine.

#115 of 130 Re: Mileage [lgandad] '97 Outback [kidali] [xwesx] [pilot1226] [ateixeira] [pilot1226] by xwesx

May 26, 2011 (9:09 am)

Replying to: pilot1226 (May 26, 2011 8:32 am)
If your trip computer is anything like the trip computers on the Forester and Impreza, you'll likely find that it is between 1 and 1.5 mpg on the optimistic side.

#116 of 130 Re: Mileage [lgandad] '97 Outback [kidali] [xwesx] [pilot1226] [ateixeira] [pilot1226] [xwesx] by ateixeira

May 26, 2011 (9:48 am)

Replying to: xwesx (May 26, 2011 9:09 am)
That is typical, but I had a Tribeca for a week, and oddly enough it read 0.6mpg LOW! Strange.

#117 of 130 Re: Mileage [lgandad] '97 Outback [kidali] [xwesx] [pilot1226] by occking

May 30, 2011 (10:14 am)

Replying to: pilot1226 (May 25, 2011 9:01 am)
I have mad my 11 outback since Oct 1. For first 10,000 miles, I did not reset one trip odometer and it read 28.2 mpg. I am now over 9000 miles since then, and, again, it reads 28.2 mpg. I always fill the tank myself, and always "top it off", so I know my actual mpg per tank are very accurate. Probably cutting it too close, on three occasions I put in 18.5 gals, one time 18.9 and the tank is supposedly only 18.5 gals.
 
At any rate, when I have a chance I will add up all the gas I have purchased for this vehicle since new (I keep good records) and I believe it will come out to just about 27 mpg, actual. Yes, everyone's statements about mileage indicated on trip comuters being optimistic is correct. I have had many vehicles past 20 years or so, and every one of them is "optomistic, and this includes a 2005 outback, 2006 Tribeca, 2009 Forester, as well as my current vehicle. I would say the actual mpg usually 1 to 1.5 mpg less than computer indicates.
 
That being said, I have averaged, per trip computer around 31 to 32 mpg on a few occasions, but the best actual mpg I have ever attained (on mostly highway driving) has been 30. If, near the end of a long trip I must fill up, then continue home for another 30 - 40 miles, I have seen the computer go as high as 34 mpg. I think that's because the previous many miles were all highway, as well as the portion of the trip back home.
 
However, if I start up following morning & it still says 34 mpg, after just a few miles, it will drop very quickly.

#118 of 130 Re: Mileage [lgandad] '97 Outback [kidali] [xwesx] [pilot1226] [occking] by ateixeira

May 31, 2011 (9:58 am)

Replying to: occking (May 30, 2011 10:14 am)
The tank may be that size. If you topped it off, portions of the rest could be in the fuel filler neck itself.

Messages Page 12 of 14

To POST a message, please Sign In.

Advertisement

Browse by Category

Browse by Vehicle
   View All Vehicles

Browse by Board
Browse by Topic
View All Topics

Edmunds Community

Advertisement