Subaru Legacy Forums

Subaru Legacy Forums (http://legacygt.com/forums/index.php)
-   Detailing, Maintenance, and Long-term care (http://legacygt.com/forums/forumdisplay.php?f=56)
-   -   Terrible MPG! Help! (http://legacygt.com/forums/showthread.php?t=202761)

kallawgt 03-03-2013 02:00 AM

Terrible MPG! Help!
 
I have a 2008 legacy GT and love it... But I am getting terrible MPG right now, about 16-17. First of all I don't think this is normal if so let me know. What could be some causes of this if it isn't normal? O2 sensor? I read something about those and how they can effect your fuel. Any help would be much appreciated!

HAMMER DOWN 03-03-2013 12:30 PM

Right foot is the biggest factor in MPG. All city 15-17, mix 19-21, all highway 27-30.

I'm 40\60 cty/hwy. Drive normal, avg. 25.2mpg, heavy on the boost, 22.7 mpg, long highway tips 28.8 mpg. My avg, mpg is 24.6 for my 120 daily commute.

Mechanical part that can effect MPG's, bad, dirty or worn out, MAP sensor, air filter, fuel injector, spark plugs, coil packs, O2 sensors, CAT's & your tune that you're running.

Mike

ttnio 03-03-2013 03:19 PM

I agreed with all of the above...You probably dont have a mechanical issue. Ease off the right foot.

kallawgt 03-03-2013 03:35 PM

I wish it was as easy as lifting my right foot... I have been easy on the gas and still get 16 average mpg! I will look into those things you said may cause this. Thanks for your help hammer down.

orndog 03-03-2013 06:55 PM

Did you just acquire this car or do you have a history of its MPG? Does it now have or has it ever had any mods?

kallawgt 03-04-2013 12:43 AM

Ive had it for about 2 months now and its been around 16-17 MPG ever since I bought it... the only mods is a SPT cold air intake, full exhaust, and coilovers.

HAMMER DOWN 03-04-2013 02:31 AM

Are you tune for you mods. This cars needs to be tune for any that not stock. For air entering the motor & exhaust exiting the motor before the mid pipe. IE; SPT cold air intake & full exhaust .

Mike

end0 03-04-2013 02:54 AM

Could also be useful if you took some logs and had someone look over them to see anything out of the norm.

OCDetails 03-04-2013 12:44 PM

I bought my '05 LGT new and I never saw better than 17 MPG. It was one of the reasons I decided to get rid of it. The non-turbo Legacy gets great mileage, but I guess there is a tradeoff with the turbo in that regard. I can get 25 mpg out of an '09 Rav4 V6 all day long. Different vehicle obviously, but still.... If I can get 25 on average out of a vehicle with the same or more power and is quite a bit heavier, then I am just surprised I can't get that out of the LGT. At least, that was my experience with my 05.

Brady 03-04-2013 03:40 PM

What kind of driving are you doing as well? I routinely see 18-19 mpg when I don't drive on the interstate for a week or two. If you have a relatively short commute to work, don't spend much time on the highway, and/or your car doesn't get much time to warm up, the mileage you're seeing seems totally reasonable.

I have never understood why people buy this car with 250-300 hp (depending on model year and tune) and are then surprised it gets similar gas mileage to that of a V8 of approximately the same model year putting down similar power.

Brady 03-04-2013 03:51 PM

@OCD ... 4 more years of technology, completely different drivetrain, and the Turbo ... umm ... encourages fuel consumption at RPM well below that of the NA RAV4. And as for weight, the RAV4 weighs in right around 100 lbs heavier comparing slush-box to slush-box.

The biggest advantage there is the extra 4-5 years of technology.

OCDetails 03-05-2013 12:32 PM

Yeah, I didn't really look at the weight numbers. I just assumed it would be heavier because of the size. But the technology doesn't really matter too much on this one I don't think. The '06 Rav4 V6 got the same gas milage as the 09 I'm comparing it to. I think it is the turbo that is eating it all up. You see that all the time when comparing turbo cars to NA cars with similar performance numbers. You sacrifice fuel economy to get the faster 0-60 and 1/4 mile times. Not that I mind. If I was looking for a fast car then fuel economy isn't necessarily on the top of the list of things I care about.

It just goes back to the basic three things you get to choose from and only get 2 of them: Fast, Cheap, and Reliable. You only get the three choices and can only have two, so what are you willing to sacrifice? I'll take Fast and Reliable any day of the week compared to what you get with the other combinations.

mmmmspecb 03-05-2013 12:56 PM

I can't wait to see Subaru's new direct injection turbo boxer motor... It's crazy what DI can do for gas mileage and power.

Turbo Cobalts are getting over 30mpg IIRC.

FYI I average about 21 MPG as well :(

AZP Installs 03-05-2013 01:36 PM

Quote:

Originally Posted by HAMMER DOWN (Post 4322446)
Are you tune for you mods. This cars needs to be tune for any that not stock. For air entering the motor & exhaust exiting the motor before the mid pipe. IE; SPT cold air intake & full exhaust .

Mike

Actually u don't need a tune for the spt intake as long as u have a stock row pipe and up on it.


-Mike Paisan

http://www.pbase.com/paisan/image/91072632.jpg http://www.pbase.com/paisan/image/14...8/original.jpg http://www.pbase.com/paisan/image/133406601.jpg http://www.whiteline.com.au/images/logos/perf1.jpg
11+ Years Maintaining, Modifying and Educating TriState Subaru Enthusiasts.
Call directly as We carry almost every manufacturer now, so before you buy parts call us.

Like us on Facebook! | E-mail: sales@azpinstalls.com | 725 Fairfield Ave | Kenilworth, NJ 07033 | 908.248.AZP1 (2971) | T-1 Certified Amsoil Direct Jobber |AIM: AZP Installs
"Race Tested, Enthusiast Approved!"

AZP Installs 03-05-2013 01:43 PM

The rav 4 and any commuter based car will get better mileage due to gearing.

On my SVX I could turn 28-30 mpg easily on the highway at 75+ mph. My sti would get 17-18mpg at those speeds.

The issue is that final 5th or 6th gear ratio. On a turbo Subie it turns 3500rpms or more. On my 335 at 80 it turns 2500rpms with 300hp and gets 26-27 mpg at 80.

Most toyotas and gm cars turn very low RPMs in the top gear and get great mileage.


-Mike Paisan

http://www.pbase.com/paisan/image/91072632.jpg http://www.pbase.com/paisan/image/14...8/original.jpg http://www.pbase.com/paisan/image/133406601.jpg http://www.whiteline.com.au/images/logos/perf1.jpg
11+ Years Maintaining, Modifying and Educating TriState Subaru Enthusiasts.
Call directly as We carry almost every manufacturer now, so before you buy parts call us.

Like us on Facebook! | E-mail: sales@azpinstalls.com | 725 Fairfield Ave | Kenilworth, NJ 07033 | 908.248.AZP1 (2971) | T-1 Certified Amsoil Direct Jobber |AIM: AZP Installs
"Race Tested, Enthusiast Approved!"


All times are GMT -6. The time now is 04:20 AM.


LegacyGT.com