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Old Apr 13, 2003 | 10:14 PM
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hi, even if i dont boot my MY97 turbo around and run under 2.5K revs, i still only get around 200 miles to the tank, and now ive just got it serviced my last tank lasted 175 miles???!!

would a ecu reset improve this? and how is this done. (i tried the jumpers and the throttle full and half but it didnt seem to do anything.

also its showing a throttle sensor error

oh yer, the only mod i have is a collins dump valve, everything else is completely stock

cheers


Sy
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Old Apr 13, 2003 | 10:36 PM
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My guess would be a dodgy lambda sensor.
Throttle sensor may be off too I suppose (wouldn't know about that) but the lambda could be misreading but still working (so the ECU wouldn't notice) - it would just give very bad economy
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Old Apr 13, 2003 | 11:20 PM
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i know the feeling m8 my my98 does exactly the same i dont know what 2 do about it
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Old Apr 14, 2003 | 07:17 AM
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sell em and buy a mondeo ghia..30 to the gallon round the houses..sold my p1 due theft miss it a lot but not the trips to shell
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Old Apr 14, 2003 | 11:53 AM
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ok, how do i check if it is the lamda senser?

cheers for the help

Sy
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Old Apr 14, 2003 | 12:38 PM
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You see if your fuel economy is cack; if it is, you're lambda sensor has probably gone

The lambda would be reading wrong but giving out correct looking readings, so an AFR meter would probably look OK (except under load when the lambda isn't used, at which point it would say 'ridiculously rich' even if it was working so may not get you very far...). But I suspect that once you'd sorted an AFR out, fitted it, etc. you'll have paid for almost as much as a new lambda sensor anyway
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Old Apr 14, 2003 | 01:46 PM
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ok sounds as if its that then. where and for how much can i get a lambda sensor for? or are they fixable?

Cheers for the help

Sy
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Old Apr 14, 2003 | 10:46 PM
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can anyone help?

Cheers
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Old Apr 15, 2003 | 06:24 AM
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bob rawle developments will post one out to u
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Old Apr 15, 2003 | 11:20 AM
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How far should a my97 Turbo be going on a tank or doing to the mile. Mine only does a little more than 200 to a tank but that is being driven hard. I am being to think now that this isn't normal ????
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Old Apr 15, 2003 | 12:05 PM
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Lose a few pounds that might help.
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Old Apr 15, 2003 | 02:36 PM
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hehe, those who live in glass houses and all that.....
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Old Apr 17, 2003 | 11:57 AM
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right, just hammered through another tank, driving really hard everywhere and i get 200 miles to the tank? same miles as driving below 2.5K revs???

does this mean for sure its the lambda sensor as the lambda isnt used when driven hard?

Cheers

Sy
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Old Apr 17, 2003 | 12:17 PM
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I think you may want to change your lambda sensor
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Old Apr 17, 2003 | 12:22 PM
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Sounds like a lamda sensor!

The one that connects into your downpipe!
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Old Apr 18, 2003 | 10:11 PM
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I also get 200 miles to a tank on a sti v5 i always thought this was normal or is it also heavy on fuel? Cheers
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Old Apr 18, 2003 | 10:19 PM
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The other possibility is the water temperature sensor is misreading. This gives similar symptoms to a lambda sensor failure.

Lambda sensor is more likely though, as they get plenty of abuse in a Scoob...

BTW I got 300 miles from the last 3 tanks in my MY96 UK - most of it motorway cruising. Usually, I get 250 miles from a tank locally - the car's never really warm.
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Old Apr 19, 2003 | 02:06 AM
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Hm.. I get about 250km from full tank to fuel light in my JDM 98 Forester, so about ... 12 mpg? Pretty nasty, until this thread I was buying all the reassurances like "oooooh turbos are always that way" and "well what do you expect for AWD in city driving". But I think its obvious now I'm looking at a sensor fault.

Is it far more likely to be the lambda sensors fault as opposed to.. the AFM? What other servicing can I do toward better fuel economy. Plugs?

Oh, where can I get a replacement lambda sensor? what kinda part number variations are there between the models, mines a JDM Forester S-tb

[Edited by Joth - 4/19/2003 2:10:03 AM]
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Old Apr 19, 2003 | 09:42 PM
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I get about 220 miles average per fill up with my MY97

However, this is not a tank-full (60 litres / 13.2 gallons)

I fill up when on the 'E' (of empty), when the car takes about £36 of super -unleaded at around 79.9p per litre.

Works out around at 45 litres used (around 10 gallons) for 220 miles, giving around 22 mpg which is reasonable for mixed driving

So for a 'tank full' I would get a bit more.

What do you base your 200 miles on;

the tank capacity of 60 litres or just down to the 'E' on the fuel gauge?

Cheers

Rich


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Old Apr 20, 2003 | 11:43 AM
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yeah i noticed that when its on empty it only takes about £37 to fill it with optimax

must have an over active empty section on the guage lol
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Old Apr 20, 2003 | 08:43 PM
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i must run it down to almmost empty then!, it usually costs about £41 to fill up with optimax,

just filled up again, and the odometer was on 197 miles. (after mixed driving.)

ive tried phoning the sugested company (bob rawle developments) but no one ever answers (tried all week)

so can anyone help me with finding a replacement lambda sensor? is it wise to go to a breakers yard?

i dont really want to spend a fortune at subaru parts just to find that its not the sensor.

Sy
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Old Apr 20, 2003 | 10:04 PM
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IMO your fuel consumption doesnt sound too bad...

Do a poll with every member of this BBS who owns a scoob of one sort or another, i bet that the 'average' milage on a full tank is between 150-180 miles.

If i listened to everyone on here i would be pulling my hair out.... I get an average of 120/140 miles per tank.. most of the scoob owners i know get an average of 200 miles with mixed driving.

What i would do is source a multimeter and check the voltage from the lambda sensor, This is how i determined that my sensor had packed up.
You can check the voltage quite easily at the ecu pin out.. at idle the voltage should fluctuate between roughly 200-850mv

Rob
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Old Apr 21, 2003 | 10:44 AM
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I get around 340 miles to a tank (50 litre fill) if I'm doing long journeys; never got below 240, & that was with 2-3 hours of 'tuning' session.

It's remarkable how many people have disfunctional lambda sensors but don't realise it, as most Subaru garages can't test for failure (well, complete failure they can, but not 'drift' which is the bad-fuel-economy bit). Think how many fail their MOTs on lambda failure - one time when it's accuracy really is tested!

I -think- (but not at all sure!) that the cost of a lambda is around £80. Which is 100 litres of fuel. And you're probably getting through around 15 litres more fuel per tank than you should be, so the lambda would be paid for in 7 tanks.

[oops - forgot to say - my car (UK MY00) doesn't actually 'use' a lambda sensor except for when it's being set up, and then it's on a wideband, which is probably largely why the economy is better than most on long journeys - but when I did use narrowband & closed loop, I still got around 290-300, which I believe is easily achievable ]

[Edited by nom - 4/21/2003 10:47:35 AM]
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Old Apr 21, 2003 | 10:48 AM
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tweenierob: funny that cos on a totally unmodified scooby turbo on parkers.co.uk is suposed to get 29.9 MPG, my one only has a dump valve, and that didnt make any difference what so ever to the fuel consumption.....

just been out in it and got it nice and hot. if i rev the engine out of gear, i can get the exhaust to pop???? its gotta be running rich right?? as its popping in an exhaust with 2 cats???

cheers

Sy

edited cos nom replied when i was typing this msg.

[Edited by SyHightower - 4/21/2003 10:52:35 AM]
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Old Apr 21, 2003 | 10:57 AM
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I run a MY00 Aust Spec, and I used to get 450 - 465km (277 - 287mi) out of about 50L. With the Link in a fairly rich tune (as mentioned by a great tuner, I might add) I am still getting 430km (265mi) out of 50L and that was with quite a few high acc and speed runs for datalogging purposes, I on average will do around 400 - 500km a week.

But then we also have a 3.9 final ratio in our cars...

Cheers
Brett
MY00 (Aust Spec)
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Old Apr 21, 2003 | 02:08 PM
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Early wrx eg mine is a 93 only have a 50 litre tank uk has 60 litre tank i get about 200-240 miles for a tank.When you next fill up ignore the cost as petrol prices vary , look at how many litres you have put in and compare this to milage , you must do this from a full tank though.

Mark
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Old Apr 21, 2003 | 04:18 PM
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http://www.guycroft.clara.net/utils/mpg.html
check this out for checking mpg
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Old Apr 21, 2003 | 06:38 PM
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well that site proves that im getting about 18mpg

hopefully getting a new lambda sensor soon now

Sy
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Old Apr 22, 2003 | 09:22 AM
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That site puts me at 23 mpg. 60 ltr tank ???? Jesus mine must run on empty for an eternity !!!!!!
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Old Apr 22, 2003 | 05:30 PM
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In your first post you said that you have a TPS check engine light. I don't know your MY very well. I put a dump valve on MY2002 WRX and the clamp that holds the recirc hose on was in contact with the TPS conector and it caused the TPS to become unpluged. This would only happen if the dump valve is mounted on the intercooler next to the throttlebody.
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