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Discussion Starter · #1 ·
Ok I have been in a boosted IS for over 3.5years now, and I have always noticed that my gas gauge readings have been off. Meaning: when I see a 1/4of a tank left I KNOW that I am actually empty. I think from ppl on the board we have narrowed it down to the fact that the Bigger Injectors are throwing off the readings.

Recently I heard from Jaman, a boosted member, and he suggested to me to leave the key turned on, but not the engine running. MUCH MUCH to my suprise Jaman fixed it w/ his suggestion...

So after 10 fill ups, 8 w/ the key turned on and 2 w/ the key out, I have come to the conclusion that this FIXES the gas gauge reading problems. Which it kinda makes sense if you think about it, the car doesn't know you have bigger injectors so the OBD II believes that everything is the same before you boosted, but if you leave the key on while you fill up the computer then reads the actual reading instead of what it thought it might be.

I have closely monitored the tank and gas guage while doing this, and I have also ran the car until it was completely empty. The gauge did its job, notifying me that when I got below a 1/4 of a tank the gas gauge light came on, 80miles after that I went empty.

I don't know if this has been discussed prior to this if so, WHoops repost, if not, Hats off to Jaman, good thinking man.
 

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Podiatrist
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If only I could drive my car I would be able refill my gas tank.
This is something I'll have to test out when the weather goes above freezing.
 

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Ok I will add something to this post cause it's very interesting.

When filling up gas, sometimes I leave the key in the "on" position and sometimes I don't. When I don't leave it on the on position, I'm usually out at 1/4. When I left it "on" last time I filled up at 1/4 left, It only filled to 12.5 gallons!

This is really cool and I will have to test it for myself. Leave the key in the "On" position while filling up. I just hope I don't run out of gas if it doesn't work! lol :lol:
 

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but gas stations tell you to turn off your engine when you fill up. :wink:

does this happen to anyone else? sometime my gas gauge will drop suddenly. let's say i'm at half tank, and then i drive a little, the gauge will drop to 1/4 tank all of a sudden. if that happens, then i know that i'm not out of gas yet and that it's reading is "normal" again. :-?
 

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oneeyejack said:
but gas stations tell you to turn off your engine when you fill up. :wink:
I think he means to keep it in the ON posisition, not with the engine on, so that the ECU is still operating....
 

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Tis could explain why sometimes my gauges seems accurate and sometimes it don't!!!!!

Sweet! Will try!
 

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Discussion Starter · #9 ·
I am not sure, this is just from my personal observations, but anything larger than the stock injectors will throw off the readings.


As for the 80 miles, well, it was 50 miles to get home once the light came on, than I sat in my driveway until the car ran out of gas.
 

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Discussion Starter · #10 ·
Yes leave the key in the "ON" position but DO NOT turn the engine on, so if you see the gauge rising when you fill that means its on, if you don't see it rising when you fill, turn the key to the "ON" position.
 

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Freelance said:
Yes leave the key in the "ON" position but DO NOT turn the engine on, so if you see the gauge rising when you fill that means its on, if you don't see it rising when you fill, turn the key to the "ON" position.
Randy I have tried this, but I turned the key to the "on" position after I started filling up my tank. I could see the gas guage moving up jerking a bit while it was filling up. Still same thing happens to me though. The dramatic drop on the gauge.
 

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Discussion Starter · #12 ·
Wxman said:
Freelance said:
Yes leave the key in the "ON" position but DO NOT turn the engine on, so if you see the gauge rising when you fill that means its on, if you don't see it rising when you fill, turn the key to the "ON" position.
Randy I have tried this, but I turned the key to the "on" position after I started filling up my tank. I could see the gas guage moving up jerking a bit while it was filling up. Still same thing happens to me though. The dramatic drop on the gauge.
Really, hmm it has worked flawlessy(i don't know if that is even a word) for me in the past 2.5 weeks that I have been doing this...
 

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Wxman said:
Freelance said:
Yes leave the key in the "ON" position but DO NOT turn the engine on, so if you see the gauge rising when you fill that means its on, if you don't see it rising when you fill, turn the key to the "ON" position.
Randy I have tried this, but I turned the key to the "on" position after I started filling up my tank. I could see the gas guage moving up jerking a bit while it was filling up. Still same thing happens to me though. The dramatic drop on the gauge.
maybe it needs to be EMPTY before doing it the first time?? not just "low" or 1/2 tank????
 

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mattssi said:
Wxman said:
Freelance said:
Yes leave the key in the "ON" position but DO NOT turn the engine on, so if you see the gauge rising when you fill that means its on, if you don't see it rising when you fill, turn the key to the "ON" position.
Randy I have tried this, but I turned the key to the "on" position after I started filling up my tank. I could see the gas guage moving up jerking a bit while it was filling up. Still same thing happens to me though. The dramatic drop on the gauge.
maybe it needs to be EMPTY before doing it the first time?? not just "low" or 1/2 tank????
That could be it too. That makes sense, but my guage seems to drop like rock from full to 3/4 tank. Then, when it hits half a tank, it drops to 1/4 and I need to fill. I was thinking maybe it was sticking, but when I turn it off it drops problem free.
 

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Wxman said:
mattssi said:
Wxman said:
Freelance said:
Yes leave the key in the "ON" position but DO NOT turn the engine on, so if you see the gauge rising when you fill that means its on, if you don't see it rising when you fill, turn the key to the "ON" position.
Randy I have tried this, but I turned the key to the "on" position after I started filling up my tank. I could see the gas guage moving up jerking a bit while it was filling up. Still same thing happens to me though. The dramatic drop on the gauge.
maybe it needs to be EMPTY before doing it the first time?? not just "low" or 1/2 tank????
That could be it too. That makes sense, but my guage seems to drop like rock from full to 3/4 tank. Then, when it hits half a tank, it drops to 1/4 and I need to fill. I was thinking maybe it was sticking, but when I turn it off it drops problem free.
I experience this mostly... stupid cars
 

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mattssi said:
Wxman said:
mattssi said:
Wxman said:
Freelance said:
Yes leave the key in the "ON" position but DO NOT turn the engine on, so if you see the gauge rising when you fill that means its on, if you don't see it rising when you fill, turn the key to the "ON" position.
Randy I have tried this, but I turned the key to the "on" position after I started filling up my tank. I could see the gas guage moving up jerking a bit while it was filling up. Still same thing happens to me though. The dramatic drop on the gauge.
maybe it needs to be EMPTY before doing it the first time?? not just "low" or 1/2 tank????
That could be it too. That makes sense, but my guage seems to drop like rock from full to 3/4 tank. Then, when it hits half a tank, it drops to 1/4 and I need to fill. I was thinking maybe it was sticking, but when I turn it off it drops problem free.
I experience this mostly... stupid cars
Matt, it is a small price to pay for 500 ponies. :)

(Thinking out loud) Maybe I should count horsepower in quarter horses rather than full horses. That way I could have 2000 quarter-horsepower. Or rwQhp. What, did I say that out loud (Brain restarts and tells me I am typing).
 

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Since my trip to toyomoto my gauge has been correct. I haven't been doing anything different either. I'm still very hesitant to run it out of gas, but I've had an accurate reading ever since.(and I haven't been leaving the key on).

I can't explain it, though I wish I could.
 

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IS_Dude said:
Since my trip to toyomoto my gauge has been correct. I haven't been doing anything different either. I'm still very hesitant to run it out of gas, but I've had an accurate reading ever since.(and I haven't been leaving the key on).

I can't explain it, though I wish I could.
the gasoline tank ghost. :eek:
 

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IS_Dude said:
Since my trip to toyomoto my gauge has been correct. I haven't been doing anything different either. I'm still very hesitant to run it out of gas, but I've had an accurate reading ever since.(and I haven't been leaving the key on).

I can't explain it, though I wish I could.
"Toyomotos shift kit upgrade mysteriously fixex gas gauge problem, new at 11"
 
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