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Old 03-08-2012, 11:12 AM   #21
Mango
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Originally Posted by jasonbimmer View Post
well when the car is stopped, you cant really calculate MPG anymore because you cant divide by 0. thats why BMW decided just put the needle at far left.
i dont think nobodys debating that. thats not the op's issue, apparently. he's saying his MPG is in the MIDDLE while stopped. not extreme left (0) or not extreme right (50)

is this correct, OP?
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Old 03-08-2012, 11:17 AM   #22
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OK nevermind. for some reason i thought 0 was at the very end. turns out its 12. Looks like at idle though its at 50 (to the left) so still i think something is wrong if its at the other end
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Old 03-08-2012, 11:21 AM   #23
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Originally Posted by E46Mango View Post
JD, the OP says his gauge is at 12 mpg while stopped, right? If so, that is not normal. And AFAIK, the MPG gauge is vacuum-controlled (similar to a boost gauge on turbo cars) so what do you mean there's nothing to fix? Wouldn't a compromise of the vacuum line mean the needle isn't pointing where it should be? Maybe I'm reading your post wrong or just misunderstanding the OP's problem.
I read that the needle swings to 12 before the stop, then swings back to 50. This is normal behavior.

The needle is not vacuum controlled. It behaves like a vacuum gauge, but it isn't one. If it was a vac gauge, then it would not drop to 12 and then swing back to 50 when the car comes to a full stop. It is an electronic gauge that gets input from the computer as the computer calculates the speed vs. the fuel demand. As the speed changes and the demand remains a constant, the needle swings. If the vac was driving the gauge, then the speed would not have any bearing on the indication.

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Old 03-08-2012, 11:23 AM   #24
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OK then yes if thats the case that is correct. I never pay attention to the needle while stopped anyway cause there's no point. Fuels being burned for nothing anyway.
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Old 03-08-2012, 11:28 AM   #25
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i dont think nobodys debating that. thats not the op's issue, apparently. he's saying his MPG is in the MIDDLE while stopped. not extreme left (0) or not extreme right (50)

is this correct, OP?
There is no reason to divide by zero. If the car is not moving, the fuel consumption is the fewest miles per gallon possible, not the most. The gauge should be programmed to be buried at the minimum reading, not pegged at the maximum. It's a simple line of code that somebody overlooked. Indeed, perhaps it is a setting that the GT1 can make, but for whatever reason the setting is set by default to what we see instead of what logic says we should see.

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Old 03-12-2012, 10:32 AM   #26
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Thats exactly what is happening to mines...sorry for the confusion guys

If its normal like you said then I have nothing to worry about. I just could have sworn it never did this before.

and also it stops doing it when the car is worm....so I dont know. Whatever, Im just someone who likes to have their car working 100% no matter how dumb or useless the feature that isnt working is

I will look at that hose that people mentioned to see how it looks once the weather gets better. Thanks for the help guys





Quote:
Originally Posted by jdstrickland View Post
I read that the needle swings to 12 before the stop, then swings back to 50. This is normal behavior.

The needle is not vacuum controlled. It behaves like a vacuum gauge, but it isn't one. If it was a vac gauge, then it would not drop to 12 and then swing back to 50 when the car comes to a full stop. It is an electronic gauge that gets input from the computer as the computer calculates the speed vs. the fuel demand. As the speed changes and the demand remains a constant, the needle swings. If the vac was driving the gauge, then the speed would not have any bearing on the indication.
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Old 04-24-2012, 05:38 PM   #27
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Mine has been doing the same thing recently, but it doesn't make it all the way to 12, it goes to 30, then back to 50. (when i am coming to a stop, and it should be resting at 50) Started this a few weeks ago, really annoying. worried it could be a bigger issue...
EDIT: My car is a 2003 325i
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Old 09-27-2012, 11:59 PM   #28
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Here is the fix for the Hissing. I did this and it works great

http://forum.e46fanatics.com/showthread.php?t=533035
i ripped apart ther trim under my car, i could not locate the blue and black hose that may have damage to it. i have all the suspecting signs pointing towards a vaccums leak just cant locat the hose

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Old 09-28-2012, 12:02 AM   #29
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I don't think the whoosh sound is normal. The vacuum line under the dash panel gets chaffed over time by the steering column and develops a hole (vacuum leak). The solution is to cut the damaged part out and install a plastic T-fitting. AFAIK, this fixes the whoosh sound and/or any vacuum leaks. I haven't had a chance to get to it yet.. maybe today I will!!
did you ever do this?
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Old 09-28-2012, 12:10 AM   #30
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I HAVE that same whoosh sound but i cannot loacte the vaccum hose,
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