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I just bought a '08 Legacy 2.5GT Limited and it is not meeting the MPG levels on the window sticker. It says that it is suppose to be 18 MPG/24 MPG (city/highway). However, I am averaging 13 MPG. But sometimes, it reaches 35 MPG when I am driving...I wonder what would be the problem. Maybe it might be that the engine needs some running time... any other ideas on what is going on?

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how would it be related to my right foot except I know it is on my gas pedal?
I do think that's the point. :)

 

How are you running the SI-Drive -- "Intelligent", or "Sport Sharp"?

 

How are you determining average MPG -- calculations based on several tanks of gas and odometer readings, or readout?

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If you do the math by hand, does it match what the computer is telling you? I'm the type that doesn't always trust what a computer readout tells me.

 

How many miles have you driven so far? I've always heard that a brand new car won't get as good of MPG as one that has some miles on it and is properly broken in.

 

I don't think you can really get any sense of your gas mileage until you've run 3-5 tanks through-- you said you just got the car, right?

 

Remember that when you calculate your gas mileage by dividing the number of gallons you added into the number of miles driven, you're getting an average. Your computer readout is probably much closer to real-time, showing you how MPG fluctuates as you drive based on engine load, temperature, driving style, etc.

 

The window stickers are an estimate only--even though the new test is more realistic, I doubt that too many people drive the way the test is conducted. There are just way too many variables--quality of gas, ambient temperature/humidity/barometric pressure, engine temperature (coolant, oil, etc.), load, weight, and the list goes on and on.

 

In any case, I'd say if your pen-and-paper calculations over 4-5 tanks of gas match the car's computer average and it's still way low (and 13.5 sounds low), then I think it's worth getting checked out.

 

Brian M.

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I have had the car for 3.5 weeks. I have driven it for 280 miles....it was driven 150 miles before I got it. I have filled it 2.5 times. The car holds 14.5 gallons of premium gas. I might still talk to the service department at the regional Subaru dealership.

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Gas mileage by the computer is accurate for that place and time, not over the entire tank. If i dirve 1.5 miles to the gym, i get 11 mpg. If I drive to my best freinds house, 22 miles away, i get 28 mpg, and to my other freinds I'll get 19.

 

Also It takes a while for your engine to get broken in. Fuel mileage will come up. Do the math manually over a few tanks.

 

And yes your right foot has a lot to do with it. If you want gas mileage drive like there is an egg under your right foot, if you want fun, break the egg.

 

nipper

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I am getting my average MPG from the car's computer, which is averaging 13.5 MPG. I drive the car in automatic or the sport sharp mode. I rarely put it in sport or intelligent mode.
You're apparently demanding performance but expecting good gas mileage. Unfortunately, the two don't tend to coincide. It's obvious that the engine is capable of decent mpg, since you saw 35 MPG at times.

 

The shift points, etc., of "Sport Sharp" might be making you happy :burnout: , but that mode uses the most gas. Try "Intelligent" mode for a while, take it easy on the gas pedal, and see what happens.

 

EDIT: Of course, make sure your tires are properly inflated. I assume you aren't carrying a ton of stuff around, but if you are, lighten the load. You might see a slight improvement in gas mileage as you put on "running time", but don't expect much -- the days of roughly finished parts that caused excessive friction and needed to be broken in are mostly gone.

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I am not carrying any load. I am not expecting much (35 mpg) but the mileage seems to be low and that is why I am slightly concerned. If it gets to 35 for a moment or two, that is great. In terms of the gas pedal and my foot, I am very light on the accelerator. I will still give the regional dealership a call and ask them.

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I have had the car for 3.5 weeks. I have driven it for 280 miles....it was driven 150 miles before I got it. I have filled it 2.5 times. The car holds 14.5 gallons of premium gas. I might still talk to the service department at the regional Subaru dealership.

 

Am I reading this correctly? Your new car has approx 500 miles on the odometer and you're expecting optimum fuel economy? If that's really the case, I'm sorry, but you have an unreasonable expectation. Fuel economy should be measured after the engine is thoroughly broken-in, that is, after you've driven at least a few THOUSAND miles. New engines, transmissions, and differential components are tight when new resulting in higher friction. If the "check engine" light does not come on while driving, the engine control systems, fuel injection, emission system , and transmission are operating within their designed parameters.

One additional item: even though the EPA has revised the way they calculate fuel economy for 2008 (notice how MPG ratings went down for EVERY 2008 model?) you still don't drive under ideal conditions all the time. You stop, you go, you encounter hills, slow traffic, the list goes on and on. You also mentioned you live in a small town. Does that mean short-trip driving for you?

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the suggested mpg rating you saw on the window sticker is not derived from a odometer based "avg mpg reading done by the car computer"

 

It was derived by math, over many many tankfuls of gas, like probably 10,000 miles average. So, drive your car for 10,000 miles, keep track of every single gas fill, the number of gallons you put in the tank. then divide the number of gallons by your 10,000 miles, in which time the car's engine will be broken in and will give an accurate true to life mpg

also, what brand and grade of gas you pump into it will affect mileage. try using something other than the lowest octane gas if you want better mileage. try a name brand gas, not the local convenient store gas.

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It is not good to assume things until you really know. I figure it out so no need to....The break in period is approximately 1000 miles. The average MPG is over 500 miles is correct. But it was driven in Beaverton, Oregon before I got it. All I need to do is reset after each refilling my gas tank. Right now, the average is 18.2 MPG and that is going over a distance 20 miles.

 

In terms of fuel type, I have to use Premium level and no lower. My car is turbo-charged.

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Sorry to hear you’re getting bad gas mileage on your Legacy Turbo.

 

There are a few things at work here IMHO:

 

1) The TANSTAAFL principle. “There [aint] no such thing as a free lunch.” You have a terrific car but fun does come at a price. Sport Sharp isn’t cheap. As a WRX driver, I was getting horrendous fuel economy until I’ve learned how to stop being turbo/boost happy. I’ve found that when I don’t give my passenger’s whiplash, I get better fuel economy:rolleyes: . It’s not as much fun for me though.

 

2) If you do a lot of short hop driving in a small town, your engine doesn’t reach optimal operating temperature and you’ll get terrible gas mileage:

 

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

Combining errands into one trip saves you time and money. Several short trips taken from a cold start can use twice as much fuel as a longer multipurpose trip covering the same distance when the engine is warm. Trip planning ensures that traveling is done when the engine is warmed-up and efficient.

 

3) “You’re actual mileage may vary.” I don’t recall if they still put that caveat on the EPA stickers. I’ve long since stopped trusting the silly EPA figures on the car stickers. I think of them as more of an “ideal driving mpg” and use them to compare and contrast the expected fuel economy of difference car models.

 

Don’t feel too bad. Premium gas in Chicago is over $4.60 a gallon now. I haven’t checked it in the last 5 minutes so it’s probably gone up already…

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A sales person at the regional Subaru dealership has a GT and he recommended that I reset it after fill up. I moved to using Intelligent or automatic. When I am out running errands, I try to do 3-4 at a time. Your gas price for your WRX is higher than mine....I am at ~$4.11 at the moment.

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Reset the mileage readout, since the cars are started and stopped so many times prior to delivery, the mileage readout is way off. When I do PDIs (Pre-Delivery Inspections) on the new Subies, they always read like 4-10 MPG, but if I reset it before I do the 5 mile test drive, it will show 18-20 mpg by the time I get back to the dealership.

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It could be due to the 10% ethanol gas you're running in the car. All grades of Oregon gasoline are now E10 year round.

 

I used to get an average of 320 miles per tank during the summer when the gas didn't have any ethanol in it. Now that everything is E10 I'm getting about 280 miles to the tank.

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It could be due to the 10% ethanol gas you're running in the car. All grades of Oregon gasoline are now E10 year round.

 

I used to get an average of 320 miles per tank during the summer when the gas didn't have any ethanol in it. Now that everything is E10 I'm getting about 280 miles to the tank.

 

We've had it in NY for over 20 years and never an issue.

 

It's been around for a long time now, your just late to the party.

 

nipper

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Re the ethanol gas: breaking in a car on ethanol gas seems to take longer, but the engine seems to wear better once it's worn in. I've always noticed a difference between the ethanol/MTBE gas found in Arizona and the regular old unleaded usually run in the Northwest stations for part of the year. Alas, those days are gone.

 

Forget that dash MPG indicator! I once saw a 55+ reading on Aircraft-engineer's Dodge Caravan - the BIG one that could hold the kitchen as well as the kitchen sink. No way was that behemoth getting 50+! I was going down a hill, in the rain, coasting, though. I was right - the next tank, averaged out, was only 23.5 or so. Just because it states you're getting ** that very second doesn't mean it's true. Ignore it.

 

As others have said, wait until you're over 1000 on the odometer and then average your total miles driven with your total gallons pumped. Even with the *unknown* nature of the drives taken before you bought the car it will give you a good idea what you'll get down the road.

 

Check the air in your tires - new ones seem to need more air as they get broken in as well. That way you'll also catch the usual factory 'oops' of a misbalanced tire. One needs air more than the others? Squeals as you corner or feels wobbly in the wheel? Check the balance. Of the last 2 dealer-new cars I've gotten, both have been 'blessed' with bad balancing - and one with a bad alignment!

 

Enjoy your new Subie (even if you start to gasp at the cost of the fuel)

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We've had it in NY for over 20 years and never an issue.

 

It's been around for a long time now, your just late to the party.

 

nipper

 

Huh?

 

Ethanol blends of gasoline have a lower energy content per unit volume than the gasoline used to develop EPA mileage sticker ratings - even in NY.

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What I find rather puzzling is why folks who purchase cars with turbo engines in this time of $4 a gallon gas (and headed far, far higher) are concerned about low gas mileage.:-\

Each time the turbo is activated, the car becomes a gas guzzler (requiring premium gas, at that!). And if you're trying to avoid using the turbo to save fuel costs, why did you buy a turbo-engined car in the first place? Subes, being AWD vehicles, are not the thriftiest on gas, anyway.

As they say, "if ya wanna play, ya gotta pay". You've paid, what, an extra $1k for the turbo engine model? Ok,

so you're gonna have to pay more to run it, as well.;)

Anyway, you really won't know what the best gas mileage your car is capable of 'till you've put, maybe, 5k miles on it, even though Subaru says that it's broken in at 1k miles. It takes a few thousand miles more for everything engine/drivetrain related to really come together, to really reach it's optimum point.

That's my tuppence, anyway.:)

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