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Was wondering if anyone else has had this issue and could point me in the direction of a fix.
My fuel gauge is working and on fill up goes to full, after a bit of driving it starts coming down as it should, however after it gets right about to 1/4 of the gauge it goes immediately back up to full. demonic possession or did I wire something wrong? Tried reversing the sending unit wires and then the gauge doesn't work at all.
My personal notes from some testing - Subaru factory donors have 2 fuel sensors, main tank and secondary tank (left and right halves of saddle style fuel tank). In factory cars they are wired in series, each sensor is about 50 ohms empty and 1 ohm full, so they add up to about 100 ohms empty and 2 ohms full.
I used my own makeshift setup with donor sensors, so if you have sensors from some other source, you need to pass that on and someone who has been there can help.
Looking at 2002 Impreza wiring print, these are the Fuel Level Sensor, connector R58 and Fuel Sub Level Sensor, connector R59. If you installed both sensors and connected in series then you should get that 2 ohms full and 100 ohms empty across the two leads that end up at the combination meter. Locate the two leads, disconnect at least one of them and measure ohms across the tank side circuit (i.e. measuring just the resistance from the sensor pair). At any particular fuel level that you think you have, then you should have a resistance between 2 - 100 ohms that is representing that fuel level. (half full about 50 ohms. 1/4 full about 75 ohms and so on.) Unless you have a failed combo meter, not very likely I'd bet, your sensor setup is mis-wired, bad sensor or arm hanging up somehow - maybe.
Others may have had this exact problem and can give a different reason for all I know.
Interesting. My 818 is running the Boyd tank with 340 stealth pump, i'm not using the stock sending unit or FFR tank, but im assuming this would still be my issue if the sending unit from boyd is only showing 1-50 ohms as well.
I'll run down to the garage and measure the ohms right now.
Ok so sender out and on the meter i get 1.6ohms with the float all the way down and 51.6 with the float all the way up. I only have one fuel sensor so how do you correct this to range from 2-100?
Since it is a mismatch of exactly 2, some electrical engineer might be able to tell you how to add a resistor and get what you need, but I’m not sure. You can always use a FuelLink
https://www.summitracing.com/parts/c...BoCltwQAvD_BwE
aquillens post reminded me i was using the boyd fuel sender and i found an old thread about how Boyds fuel senders are backwards. Flipped the float around so it reads 100 ohms empty and 2 ohms full and boom! working! Thanks for kicking my rusty brain into gear.
I was in the same boat, only had one sensor. I ended up going to the savage yard to get the one I was missing. I could not find an easy way to double the resistance throughout the sweep range.Quote:
Originally Posted by Soon2B818
My $0.02