2006 Impreza 2.0i - Excessive Fuel Consumption (Please Help!)

Jake · Post by **Jake** » Mon Oct 22, 2007 2:25 pm

Hi there,

This is my first post so pls. bear with me if it is a bit long! (I also noticed another post about fuel consumption but I think it related to an older model of car)

I have a 2006 model Impreza 2.0i (about 18 mths old) and bought it brand new. Pretty much ever since I bought the car, I have had enormous trouble with fuel consumption. I have taken the car to 2 different subaru dealers over the course of the last 18mths and have had the problem looked at on every time I get it serviced and another time which was 'off service' cycle.

I have 2 friends who have roughly the same model and they both regularly get about 100km's more per tank than I do. Here is the problem.

I struggle to get 400km's to a tank and average 350-375km's city driving. I love the car, it is a great drive etc etc but cannot sustain this poor fuel economy (especially given current petrol prices).

As another line of enquiry, I called yet another Subaru dealer and asked what they would expect to get from the tank and they said at least 450km's (city) and up to 550km's (country). I have never got 450km from the tank - ever.

I am getting no solutions from Subaru and am at my wit's end as every time they look at it they keep telling me there is absolutely nothing wrong.

Any help on this would be greatly appreciated as I do not want to sell this car but I am quickly running out of alternatives!

Thanks
Jake

Post by **Alex** » Mon Oct 22, 2007 2:47 pm

lead foot cos its only a 2.0L??

my liberty is 2.0L and i get about 550km from a tank of country driving, and not much less in city driving.

alex

YouTube · Post by **El_Freddo** » Mon Oct 22, 2007 3:00 pm

Hey Jake,

Welcome to the forum!

First off, did the dealership tell you distances for a manual or auto? If they told you for a manual and you have an auto you could expect a drop in fuel economy from those figure to what you're getting.

That figure you're giving sounds about right, depending on your driving.

Another question: How many litres of fuel do you usually use to fill the tank when it shows empty? My L still has 20L in the tank when its on the E. You may be getting a reasonable amount of K's to the amount of litres you're using.

Give us some figures of distance travelled between filling up and how many litres you put in the tank to fill it. This will give you accurate figures of Km/L of fuel used.

I've kept records of all fuel gone into my car since i've had it, good to beable to average out the fuel use (only when completely filling tank every time).

Cheers

Bennie

Post by **Alex** » Mon Oct 22, 2007 3:02 pm

a 2L impreza should be using wayyy less than that. They are very economical

alex

vincentvega · Post by **vincentvega** » Mon Oct 22, 2007 3:04 pm

"per tank" is not a real useful way of looking at it.

work out how many litres you are using per 100km and post back here. You should be getting roughly 8L/100km (manual) or 10L/100km (auto) in the city

Gremlins · Post by **Gremlins** » Mon Oct 22, 2007 3:20 pm

I also have a manual 2.0i and would say 450k's would be about the most you'd see if you were doing city driving before the low fuel light comes on. Low fuel light turns on at around 40L used (Tank is only 50L). One thing I have found is the aircon sux (both in terms of power and fuel consumption), so if you regularly use the aircon and like to give it a bit of a boot I could understand you'd be down around the 350 to 375km's on 40L, especially if the car is auto.

Jake · Post by **Jake** » Mon Oct 22, 2007 3:45 pm

Thanks for the insight... a few extra data points.

I would say that I would be getting somewhere between 10L/100km's and 12L/100km's (based on recent numbers) city driving. I would average around 375km's and would usually fill the tank up with about 42 litres of petrol. I am often at around 350km's on a tank when the fuel light comes on (specs say that fuel light comes on with 10L spare)

Also, I have tried (on advice from Subaru) driving it harder as well as softer with no discernable difference.... also have had the engine computer reset and a software upgrade...

any further help more than welcome!

Jake · Post by **Jake** » Mon Oct 22, 2007 3:46 pm

p.s. it is a manual as well

Ben · Post by **Ben** » Mon Oct 22, 2007 8:17 pm

How far are you driving it to work and back?

I know it's not a impreza (or EFI) but my brumby spend 95% of it's driven time with the choke on, I get piss poor economy (240km from 3/4 tank at the moment) because of this. If you only drive 2-4kmto work and then the same back I'd expect the economy you are getting.

Gannon · Post by **Gannon** » Mon Oct 22, 2007 8:42 pm

Interesting point ben.

If the car spends most of its time below operating temp, its always gonna be running rich, thus using more fuel.

That could actually explain my crappy economy too, im only 7 min from work

littlewhiteute · Post by **littlewhiteute** » Mon Oct 22, 2007 8:49 pm

Jake,

What fuel are you using?
I have done my own study with "fuel consumption" customers and have found the following:

Those that use ULP get average figures. PULP users get average to above average. And those that use E10 or any "brew" (unknown to them) get below average.

For the E10, it works like this: petrol has a stoichometric A/F ratio of 14.7:1.
If you blend in Ethanol which has a stoich of 9.5:1 then the O2 sensor sees this as lean and puts more fuel into the engine to correct the lean condition.
Then fuel economy drops, so if you aren't using PULP I'd switch to it.
May cost more but cents per km should be less.
Ethanol is grain alcohol, generally sugar cane, methanol is wood alcohol, A/F of 6.5:1.

Cam · Post by **Cam** » Tue Oct 23, 2007 7:56 pm

Dunno if this helps by my rs legacy gets around 400 - 450km tank (11L/100km) around town and its auto and a turbo... that's usually running on pulp tho. thought the n/a's would be a fair bit better than that... subaru quotes less than 10l/100km i think...

90brumby · Post by **90brumby** » Tue Oct 23, 2007 8:02 pm

ran the brumby on PULP filled the tank to the very top 50 somethin liters n i got 365ks n it stoped the brumby is a runnin 30inch tyres L sereis gbox with a fresh ea81 with a cam thats the basic mods

EDIT SORRY TO TAKE IT OFF TOPIC

have u had o2 sensor checked if thats not wrkin properly it will over fuel the car
does the exhaust look like it is over fuelin

Matatak · Post by **Matatak** » Tue Oct 23, 2007 8:12 pm

do some engine braking to check for overfuelling. or u culd always fiddle with the Throttle position sensor and get it running leaner urself..

but not reccomended at all lol

steptoe · Post by **steptoe** » Tue Oct 23, 2007 11:12 pm

find someone who has a portable air fuel ratio test device so it can be checked on the road for stoichometric efficiency controlled by oxygen sensor.

or not buying ethanol blended with your petrol are you ?

try 98 just once or twice and see if you get an improvement.

measure rather than guess litres per 100 please.

I filled my 'empty' 60l tank the other day and it took 44 litres dunno how many kms but feels like it is chewing the juice - next fill will reveal the pain of an old turbo auto L series that can do 3350rpm at 100kmh

YouTube · Post by **El_Freddo** » Wed Oct 24, 2007 3:59 pm

steptoe wrote:next fill will reveal the pain of an old turbo auto L series that can do 3350rpm at 100kmh

Ouch! It hurts already...

Gremlins · Post by **Gremlins** » Thu Oct 25, 2007 8:15 am

I remember when I first got my L-series wagon and it was n/a auto with 185/65/13's it would sit on 4000 rpm at an indicated 110km/h in top gear. Economy was still fairly decent even at those revs.

Also, just filled up my 2.0i and the fuel consumption was 7.55 L/100km with probably 75% country, 25% city work and fairly much using the aircon the whole time.

Ben · Post by **Ben** » Thu Oct 25, 2007 1:42 pm

I filled the brumby today.

Odo read 236km
(Speed at 100 indicated is 110 on GPS)
So adjust up to suit = 259km

Put 39.93 litres in

39.93 / (259/100) = 15.42 litres per 100km - this is about the same as what the Outback (H6) gets in general running about duties also.

I am going on a good length trip mid next month so will get the chance to see what it is like on open road (I expect 9 ish)

littlewhiteute · Post by **littlewhiteute** » Thu Oct 25, 2007 7:12 pm

I regularly get about 500km/42-45 litres. 8.4 - 9L/100km

steptoe · Post by **steptoe** » Fri Oct 26, 2007 12:02 am

Cheap Grief delivered 404km to 44 litres which equates to 25.9 miles per gallon. That was some mixture of driving there and feel i can improve on that (keeping the green dash light off ! )

15 litres per hundred out of a Brumby !! a two tonne territory auto awd averages about that !!!