Unfortunatly my track season is now over and its time to make the list for the improvemnets to be made to the car over the winter. At the tops of the list is a gas guage. I'm tired of trying to calculate usage,,,, mileage etc. My car is a 1995 325is with all the stock wiring removed and a custom dash installed. I'm running a G2X data system and their guages but unfortunatly they don't offer a a fuel level guage. I have the original wiring in place to the fuel pump (in tank) and need to find an aftermarket guage that will work with whatever signal the sensor puts out. Any ideas....?
Thanks,
Scott

Someone... Anyone...?

http://store.summitracing.com/egnsearch.asp?N=115+400442+300173&autoview=sku

Add the matching level gauge and mount on your dash cluster. That sending unit does look too long (deep) to work in a BMW tank, though. Maybe change to a fuel cell that has a level sender built in, or add your own to a cell?

If you are industrious enough you could wire into the factory sender (assuming you still have a factory tank) then try to find an aftermarket fuel level gauge that works with the same range that you measure across the factory sender (a level sender usually has a potentiometer with variable resistance that translates to the level from the float).

sorry, not much help.

This is what I have: The TL25 http://homepages.ihug.co.nz/~bvdb/tl25.html

It works with the OE sender, but only 1 of them, not both (the range it not right for both). So, you will know about how much fuel you have, but not exactly since if the fuel sloshes to the other side of the tank, you get inacurate readings.

Thanks for the replies. Does anyone know the full / empty ohm outputs for the stock sender?

OK... so after a little more research I think I've got it. Both senders put out 10ohms at empty and 250 ohms full. I think I'm going with a programable guage that allows custom programs like the Autometer 6114. Install it, hook it up set reading with an empty tank then set reading with a full tank and its programed. This also should allow me to set my "Empty" mark at not quite empty.
Thanks for the help and direction.
Scott

OK... so after a little more research I think I've got it. Both senders put out 10ohms at empty and 250 ohms full. I think I'm going with a programable guage that allows custom programs like the Autometer 6114. Install it, hook it up set reading with an empty tank then set reading with a full tank and its programed. This also should allow me to set my "Empty" mark at not quite empty.
Thanks for the help and direction.
Scott

Just realize that you can only use 1 sender for the gauge, since the Autometer gauges only go up to 280ohm (same as the CruzPro actually). I have yet to find one that goes up to 500 ohms for full (the senders are added to get a ftrue reading on the OE gauge).

Would this work for an E30 then since the E30 only has one sender? I don't know the range for the E30 though, I'm assuming it's the same as for the E36. Anyone?

Just realize that you can only use 1 sender for the gauge, since the Autometer gauges only go up to 280ohm (same as the CruzPro actually). I have yet to find one that goes up to 500 ohms for full (the senders are added to get a ftrue reading on the OE gauge).

Can't you just build a circuit to divide the resistance by 2 and connect that to the gauge? There are a lot of engineers on this forum, find an EE and have him tell us how this is done. :stickoutt

Carlos.

Would this work for an E30 then since the E30 only has one sender? I don't know the range for the E30 though, I'm assuming it's the same as for the E36. Anyone?

Bentley is your friend, fuel level senders testing will surely have a table with resistances listed. I don't have my E30 one handy to tell you what they are.

Carlos.

Bentley is your friend, fuel level senders testing will surely have a table with resistances listed. I don't have my E30 one handy to tell you what they are.

Carlos.

Uh, yeah, good point. Now if I could find the damn Bentley....

Can't you just build a circuit to divide the resistance by 2 and connect that to the gauge? There are a lot of engineers on this forum, find an EE and have him tell us how this is done. :stickoutt

Carlos.

Sure ... build 2 and I'll buy one :) I looked briefly into a resistance divider circuit, and I remember giving up early (I fear tiny bits!)

Jack,
It's funny you bring this up now... Just yesterday afternoon, I measured the resistance on my old level sender from the e30... I don't remember the exact numbers, but it was in the range of 55 to 160 ohms, or so... I'll look it up again to confirm what I saw. (this was taken from my properly working sender removed from my car when I went to a fuel cell)
Guess why I was curious.... I'm sick of guessing the fuel level in my cell, too...
I do have to admit, though, that the fuel prssure gauge on the dash is a very nice thing and is helpful since I don't have a level gauge...
Get a stutter, glance at the pressure, if low then gas level is low... no way to anticipate, though.
BTW, I hope to respond to your e-mail alter today... I've been away.
Thanks.


Uh, yeah, good point. Now if I could find the damn Bentley....

Jack,
It's funny you bring this up now... Just yesterday afternoon, I measured the resistance on my old level sender from the e30... I don't remember the exact numbers, but it was in the range of 55 to 160 ohms, or so... I'll look it up again to confirm what I saw. (this was taken from my properly working sender removed from my car when I went to a fuel cell)
Guess why I was curious.... I'm sick of guessing the fuel level in my cell, too...
I do have to admit, though, that the fuel prssure gauge on the dash is a very nice thing and is helpful since I don't have a level gauge...
Get a stutter, glance at the pressure, if low then gas level is low... no way to anticipate, though.
BTW, I hope to respond to your e-mail alter today... I've been away.
Thanks.

Cool, thanks. I'll try to dig up my Bentley and see if I can find these numbers for confirmation.

Cheers.

The guy I just bought the race car off of said to just hook up an ohm meter to see how much gas I have. I need to buy soemthing and hook it up as well.