fuel mileage issue

05zx4st

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Joined
Sep 12, 2011
Messages
10
I have a 95 legacy
lifted using outback struts,225/70/14 all terrains.
went to the outerbanks a while back,got 23mpg there.
while there had to drive through some flooded roads,and felt like my o2 sensor was whacked out cause of the water.
On the way home,averaged 13mpg,so I replaced the o2 sensor and that helped out the driving issue,butstill only manage 15mpg.have a knock sensor code,have had it the whole time though.I cleaned the maf,egr,pcv. ordered a knock sensor,should be here this week.
any insight on what may be what's up? Sometimes have a fluctuation idle as well.
 
Did you have knock sensor code before the flooded roads?
 
Have you checked out your air filter? If that is gummed up with all sorts of crap, that could rob you of all sorts of gas mileage / power.

My CEL comes on it seems every other week for what it says is the knock sensor. Comes on for a day or a driving session, then goes off and i don't see it again for another week or so with no noises or apparent change performance. I think i just need to run some seafoam through the system. I've read good things about that and the problems it cures.
 
I've done a seafoam treatment,air filter is a k&n cone which I cleaned. Im hoping the knock sensor fixes it,but if not idk what else to do.
 
Besides the mileage, is it running like crap at all? Funny thing about that knock censor, is that pretty much everyone that has talked about their check in light coming on, it has always said it was the knock censor. When the light isn't on, it won't pick up any problems in the system. I pretty much just ignore it now.
 
When I first crank it its sluggish,but besides the idle issue nothing.seems to run fine.
 
Hmm.. Have you checked all the spark plugs & made sure none of them are cracked from the high water driving?
 
Yes,spark plugs are good,wires are good.
has a pretty bad gas smell when first starting,wonder if I have a leaking injector.
 
Put some Subaru injector cleaner in your next tank of fuel.
Also, run a can of Subaru upper cylinder cleaner through the engine, as per instructions. (I'm doing this next weekend.)
 
Got the knock sensor code fixed,still garbage mileage.. threw a code for egr,cleaned it out and it came back 25 miles later..idk what else could it be.
 
Barry said:
Put some Subaru injector cleaner in your next tank of fuel.
Also, run a can of Subaru upper cylinder cleaner through the engine, as per instructions. (I'm doing this next weekend.)
Click to expand...

+1, but i use Flash Lube injector cleaner...its economical, seems to work well, ie, makes the engine run better, plus I'm sure it has an octane booster as I get a noticeable increase in power.

Used the Subie engine cleaner, got clouds of smoke but didnt really notice a change in performance, but then again i think i have other issues like plugs n leads
 
Gidday mate

After a whole 18 days owning Roo2 (2006 Fox), I have got 24.9 mpg (imperial gallons); 11.14L/100 kms. All with A/C running hard. About 50:50 city:country. A couple of kms off road in low range.

I expect this to improve as I get more familiar with the vehicle. Still have a tendency to over-rev in low gears; and change into 5th in 60 km/h zones (revs too low for efficient fuel economy ... ) - at this speed, revs in 5th in Impreza were the same as 4th in Roo2.

I also expect this to improve after the 125K service due in about 25K. I might even check (change) the plugs and set the valve clearances myself before this. Many mechanics seem incapable of accurately setting valve clearances. Roo1 came out of the factory with +/- 0.001 variances in valve clearances. I adjusted these once, and never touched them again.

Roo1 had the same set of (standard NGK) plugs for about the last 100K or more. Probably due for a change due to lack of power at above 150 kph when sold ...

Will have a better idea of Roo2's consumption in a few months time.
 
Ratbag said:
Gidday mate

After a whole 18 days owning Roo2 (2006 Fox), I have got 24.9 mpg (imperial gallons); 11.14L/100 kms. All with A/C running hard. About 50:50 city:country. A couple of kms off road in low range.

I expect this to improve as I get more familiar with the vehicle. Still have a tendency to over-rev in low gears; and change into 5th in 60 km/h zones (revs too low for efficient fuel economy ... ) - at this speed, revs in 5th in Impreza were the same as 4th in Roo2.

I also expect this to improve after the 125K service due in about 25K. I might even check (change) the plugs and set the valve clearances myself before this. Many mechanics seem incapable of accurately setting valve clearances. Roo1 came out of the factory with +/- 0.001 variances in valve clearances. I adjusted these once, and never touched them again.

Roo1 had the same set of (standard NGK) plugs for about the last 100K or more. Probably due for a change due to lack of power at above 150 kph when sold ...

Will have a better idea of Roo2's consumption in a few months time.
Click to expand...

Does this mean you've just had the 100K km service?

The best mileage (kilometreage?) I've had was bit over 9L/100kms with very conservative driving on country roads. My last lot was closer to 11L/100km :puke:
 
I went and got new injectors,same problem. Next I guess ill replace alot of vacuum lines? Lol
 
Gidday NL

Ratbag said:
Gidday mate

After a whole 18 days owning Roo2 (2006 Fox), I have got 24.9 mpg (imperial gallons); 11.14L/100 kms. All with A/C running hard. About 50:50 city:country. A couple of kms off road in low range.

I expect this to improve as I get more familiar with the vehicle. Still have a tendency to over-rev in low gears; and change into 5th in 60 km/h zones (revs too low for efficient fuel economy ... ) - at this speed, revs in 5th in Impreza were the same as 4th in Roo2.

I also expect this to improve after the 125K service due in about 25K. I might even check (change) the plugs and set the valve clearances myself before this. Many mechanics seem incapable of accurately setting valve clearances. Roo1 came out of the factory with +/- 0.001 variances in valve clearances. I adjusted these once, and never touched them again.

Roo1 had the same set of (standard NGK) plugs for about the last 100K or more. Probably due for a change due to lack of power at above 150 kph when sold ...

Will have a better idea of Roo2's consumption in a few months time.
Click to expand...

Nachaluva said:
Does this mean you've just had the 100K km service?
Click to expand...

The 100K service was done by Toowoomba Subaru (Wippels) before I bought the vehicle.

I have just noticed that this is now 12 months ago ... The vehicle was obviously sold about 3 months ago (new Vic rego for 6 months about then), probably due to the death of the owner?? So I should shuffle off to our normal servo immediately and have Ross change the oil and oil filter, at least.

The best mileage (kilometreage?) I've had was bit over 9L/100kms with very conservative driving on country roads. My last lot was closer to 11L/100km :puke:
Click to expand...

Nice to get a feel for what others are getting, gives one some idea of what to expect :).

Roo1's very best on the open road was around 7.3~7.5L/100 kms. Mostly around 8. Last trip averaged 8.9 over the 4300 kms with a couple of hundred around Brisbane while I was staying there. But A/C was on the whole trip.

Around town generally around 9.5~11 depending on traffic and A/C.

So it seems that Roo2 will probably be a little heavier on fuel, but not hugely so. The extra space (weight) and vastly improved power and torque to weight ratio have got to come at some cost IRL.

But then we are used to the Petrol Tanker's fuel consumption (aka our 2.2L Camry automatic), which is exceptionally good on the open road (around the very low 7s!), and exceptionally appalling around town (from 12~14 ... :puke:).

Still, looks like a trip to the Vet for an oil change. I can get Ross to cast his expert eye over it at the same time. Not a bad thing ... I will book it in this morning. Thanks for inadvertently prompting me about this. I had seen it, just not noticed it ...

[EDIT] Done. Booked in for the 16th. [end edit]
 
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I'd check that Subaru from Toowoomba. Any car from that area (and quite a few other areas as well) is suspect with possible water damage from the floods. Why is it so many used cars end up in Melbourne anyway?
 
Gidday Rally

Rally said:
I'd check that Subaru from Toowoomba. Any car from that area (and quite a few other areas as well) is suspect with possible water damage from the floods.
Click to expand...

I did so very carefully, thanks mate.
However, no matter how "good" the TV grabs looked, the creek that flooded there can normally be stepped over in one stride ... The ground also rises very sharply from the town centre. I went to school there for years, and my Mother's family are from there.

The car also came from out of town. There was not the slightest indication to me that it had ever even been wet inside the cabin or boot, let alone submerged.

I also checked with the Wippells Subaru Toowoomba workshop chap who told me a little of the car's history. I also have the full service records and all the original paperwork for the car when it was purchased new.

I agree with your implicit message: one should always be very wary when buying a used car. I have been 'stung' once long ago. That was enough.

Why is it so many used cars end up in Melbourne anyway?
Click to expand...

Who knows?
I think that the used car dealers are always scouring the market place and OEM dealers for vehicles that the OEM dealers don't want. They won't sell anything over about 2 y.o. these days, AFAICT.

We had a lot of "new" vehicles come on the market in Brisbane after the 1970 flood that had been fully submerged and then tarted up by the OEM dealers. It was quite a scandal ...

Thanks for your concern. AND it is a valid one that people should be made aware of.
 
Rally said:
I'd check that Subaru from Toowoomba. Any car from that area (and quite a few other areas as well) is suspect with possible water damage from the floods. Why is it so many used cars end up in Melbourne anyway?
Click to expand...

Cos we're tightarses? :rotfl:
 
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