i still don't have a clue & it's still broken...but i do know that i'm getting power from the brown/yellow wire to the sending unit...i noticed something unusual this afternoon when messing with it though....it still pegs to the full position when i turn on the ignition with the ground wire disconnected from the sending unit...
can anyone explain why that may be happening or how it's possible
My thoughts:
The Br-Ge wire is a switched ground wire -- with the tank sensor being the "variable switch" -- at full tank there is low resistance so it is fully grounded, draws the most amps and pegs the needle which needs the higher current to go to full scale reading. At low fuel levels, resistance is high, current is low, and gauge should read low. If you unplug the brown (ground) wire at the sensor, and the gauge still reads full, then that is not caused by a bad sensor unit.
One possibility is that the Br-Ge wire is grounding out somewhere allowing current to flow thru the gauge coil even when Br wire is unplugged at the sensor (which should have ungrounded the Br-Ge wire). You can test for that by disconnecting the round connector behind the instruments and then connecting an ohmmeter between one end of Br-Ge wire and the body. If there is no grounding, then you've isolated the problem to the instrument panel.
If the problem is in the gauge, I would look for a short or misire somewhere. My thought is that an open circuit would cut off the current flow and not move the needle, so I'd look for something that is allowing current flow thru the coil even when the Br-Ge wire is in open circuit.
BTW, I have a tested good sending unit (if your car is a non-Tii) I can loan you if you'd like to try it before you use the new one. If by sleeve housing you mean the plastic housing around the bottom part of the sensor, it is held on by a small nut at the bottom. Perhaps your existing sender can be repaired by replacing that (if it measures correctly on resistance reading).
Byas