fuel gauge / sensor

background:
I just started to work on my friends porsche, his dash lights went out after a garage did work on his car, when he got it back he drove it 1 mile and then he smelled electrical smoke and stoped the car and pulled it over, and thats when he noticed that he had no dash lights after that. So I wired his dash lights to a wire that is only on when his head lights are on. When I took the dash off there was about 3 bundles of wires just melted together from electrical damage.

problem:

now the fuel level gauge on the dash is not working correctly. I found out which wire controls the gauge, but I think from the wires being so bad that I should probabbly run a wire directly to the dash myself, anyone have any insight to where the sending unit itself is?

thanks in advance

the sending unit should be right on the top of the gas tank, acsessable from the rear of the interior.
though, i might be wrong... i don't think i am, but isn't that how it always is?

ah, that would make more sense, only othere sensor Ive dealt with is in my own camaro. Thank you. I will go look at that later today

Ok, I checked the sensor, doesn't seem to be getting power at all, anyone know what power goes to which prong? there is brown, yellow and a purpleish wire going to it, I assume that the brown is ground. I assume one needs to have 12 volts going to it, and the other sends a variable voltage to the gauge. Anyone able to go out and test to see which one is the variable and which one is the 12v only on when ignition on?

sorry man...
couldn't tell ya yet.

Alright, thanks, I will test the wiring further, I will probabbly have to make a custom wiring harness for this also.