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How many miles out of a tank 'til the light comes on?

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Old 03-16-2004, 05:59 PM
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Dal Heger
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I get about 420-450 miles before the light turns on (S2), or about 310 (turbo). Mixed highway city driving.

Dal.
Old 03-16-2004, 06:13 PM
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Zero10
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I get 400-440kilometers before the light comes on.
But, that's what up to 70% leakdown and 100psi will do to your mileage.
Although, I found a huge vacuum leak while it was all apart, perhaps the mileage will get better.

If I recall correctly, you can check the light by fiddling with the wires on the fuel level sending unit. I'll look it up tonight, see if I can come up with a procedure.
Old 03-16-2004, 07:03 PM
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jeeper31
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Wow. I am getting about 200 miles per tank. Figuring about 15 mpg. Thinking it should be more.
Old 03-16-2004, 07:08 PM
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Luis de Prat
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Originally posted by jeeper31
Wow. I am getting about 200 miles per tank. Figuring about 15 mpg. Thinking it should be more.
Sounds like your oxygen sensor is shot, too!
Old 03-16-2004, 07:17 PM
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jeeper31
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Originally posted by Luis de Prat
Sounds like your oxygen sensor is shot, too!
How would that change my mileage? What does it cost to replace?
Old 03-16-2004, 07:38 PM
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Luis de Prat
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It would change it considerably, since when the oxygen sensor is inoperative the car basically dumps fuel into the engine without gauging the most efficient range.

The oxygen sensor provides the DME (fuel injection brain) with a reading to ensure the right amount of fuel is used without wasting as much.

The early cars use the Bosch 11027 single wire unheated oxygen sensor. I found one at the local import auto parts store for $25, and it's going in ASAP!
Old 03-16-2004, 07:51 PM
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Originally posted by Luis de Prat
It would change it considerably, since when the oxygen sensor is inoperative the car basically dumps fuel into the engine without gauging the most efficient range.

The oxygen sensor provides the DME (fuel injection brain) with a reading to ensure the right amount of fuel is used without wasting as much.

The early cars use the Bosch 11027 single wire unheated oxygen sensor. I found one at the local import auto parts store for $25, and it's going in ASAP!
Cool. how hard to install?
Old 03-16-2004, 07:54 PM
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seb928s
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Hmm I'm getting around 16-18 city and 22 max on highway. I'm going to replace the O2 sensor plus do the vac lines hopefully I can get the mileage up. What you guys think of replaced them with used ones? I have two used ones that I got from a rennlister for free is it worth my try or should I just buy new one?
Old 03-16-2004, 08:04 PM
  #24  
Luis de Prat
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I remember from another thread that you should refrain from installing used O2 sensors. Can't remember why, exactly.

The R/R is fairly straightforward but you'll need to run the car a minute or two before attempting the removal. It's advised to spray the base with some PB blaster or WD40 to loosen the threads beforehand.

I plan on soaking mine overnight. There's also supposed to be an "oxygen sensor wrench" at auto parts stores that makes removal a cinch. Otherwise, you'll need a proper sized combination wrench, or better yet, a large enough box wrench threading the old (disconnected) wire through it.
Old 03-16-2004, 11:12 PM
  #25  
Kokopelli
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Originally posted by Scootin159
I've put about 650 miles on a tank (from full until I filled it). I never actually hit the light though, but I just got nervous and decided to fill it anyways. Now that I think of it, I've never seen the light come on before....anyway to check if it's working?
Sounds like you've been running without petrol for a while and never realized it 650miles on a tank is incredible

Damn Auckland traffic, running shoes would be a faster way to travel. From what I've read 340 miles on a tank is marginal, I'll have to keep an eye on it.

Thanks for the replies
Old 03-16-2004, 11:20 PM
  #26  
Dmitry S.
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I got about 280 miles per 17 gallons before I sold my car. At one point, I got 240 miles - about 220 miles of mountain driving, mostly above 4000 rpm and lots of load.
Old 03-17-2004, 02:04 AM
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Zero10
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I guess I should mention, that with my engine in such terrible condition, I still manage 980kms before the light comes on when I'm on the highway.
It gets great highway mileage, but all the acceleration in the city kills my mileage due to my low compression.
Old 03-17-2004, 05:08 AM
  #28  
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Last tank I got 390 miles to the light. mmm clean air filter and new plugs. Also, the early cars have the single wire O2 sensor? Could have sworn mine had 3 last time I was under there...

--Chris
Old 03-17-2004, 07:30 AM
  #29  
Luis de Prat
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Well, in 21 years there's a pretty good chance the original single wire sensor has been updated.
Old 03-18-2004, 06:09 PM
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Is this the right thing?Ebay O2 Sensor


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