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anyone else out there not able to get their gas gauge needle to go fully north when the tank is full?

i had my ip out a few weeks ago to clean things up.

someone had posted about how you can tune your voltage gauge with a little dial build into the side of the gauge. this was great advice. two weeks later, and my voltage gauge is still working great (and better than before!).

my fuel gauge has never really worked. so, when i had the ip apart, i figured i'd clean every contact i could. i noticed that the fuel gauge also has a tiny adjustment dial on it. (forgive me, i don't know what you call it. i think it's a variable resistor). for kicks, i decided to rotate it 90 deg south and see what happened....

now my gauge needle does show full with a full tank. but it also shows empty more quickly, too.

i need to take the ip out again to refinish my light reflectors, so i'm going to rotate the dial 180 deg to north and see what happens.



if anyone can find a spec on this, i think it's the solution to our problems. shouldn't be hard to hook it up to a multimeter and adjust the resistance to whatever level it's supposed to be.



(bad news is that i did manage to set off my "!" light and airbag warning. drats!)

[quote name='Brian' date='Mar 29 2006, 08:44 AM'].... i decided to rotate it 90 deg south and see what happened....

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I would think that smaller adjustments increments would be better. When calibrating a gauge, typically only a few degrees of movement is required.

yep, i agree with the minor adjustment.

there's just no way that i could think of to adjust the gauge while it was out of the car.

so i went for the grand change to see if i was on the right track. that way if it was in the right direction but too far, i'd at least know i was making progress.



it's a lot easier to calibrate the volt gauge since you can hook up dc to it and just dial it in.



i was really hoping that there was a way to measure the fuel gauge with some kind of standards and adjust it out of the car. there's probably some specs floating out there somewhere.

Good idea Brian, it sounds as if you are on the right track. I have had discrepancy with the fuel gage reading on previous 924S, 944S2 and 968 so they must all share the same gage and accuracy issues. Good luck, Bob Blackwell.

I may be off the mark, but have you looked at the sending unit that is inside the tank?



I've heard that many of them get bound up and give faulty reads after some time. Some people have removed them and cleaned them.



Jason

yep, the sending unit was my first step. much easier than pulling the ip! i cleaned up the electrical contacts and actually disassembled the whole thing. i was surprised that there wasn't much to it.

it definitely helped to clean it up. before, my gauge was sticking at 3/4 and then would drop down to 1/4. it was okay, because if the bottom 1/4 is accurate, that's all you really need.

My gauge also doesn't go all the way up. Has there been any progress with tuning the gauge or any other thoughts on how to get the needle to go all the way up?



Thanks